A version of this article previously appeared on Skillcrush, an online education program for creatives, thinkers, and makers that gives total tech newbies the tools to make major career changes.

Scott Morris, Skillcrush

If you're on the job market, you know you need to make your resume stand out. But beyond your years of work experience, what if there were some extra skills you could easily add to your resume that would increase not just your hireability, but also set you up for a higher starting salary? Time is precious and it might seem impossible, but it's actually completely doable with minimal upfront investment (I'm not talking about going back for another degree here).

So, where should you even begin? To answer this question, I picked the brains of HR and recruiting professionals to learn what kind of skills make a difference to employers—and how much of salary bump you can expect from each.

Coding Languages

Right off the bat, there are the usual suspects—HTML, CSS, JavaScript, and WordPress make a solid foundation for coding languages, and a great example of where up skilling can come into play. Being fluent in these languages maximizes your flexibility, and can provide a compelling case to employers to start you at a higher rate or salary—regardless of industry.

Xavier Parkhouse-Parker, Co-Founder and Director at digital recruiting firm PLATO Intelligence, says that if an applicant can stack a high level of HTML coding knowledge on top of the specialized role they're applying for, it's possible to aim for a 25 percent starting pay bump when negotiating a salary. Jonathan Lau, Founder and CEO of coding school directory SwitchUp, adds that SwitchUp's 2016 job outcome survey for coding bootcamp graduates found that 63 percent of graduates reported increases in salaries after completing a bootcamp program. (Among those graduates, the average gain was $22,700.) With these kind of numbers in mind, it's clear that adding some coding know-how to your toolkit is a wise investment in your career future, whether or not you're specifically interested in developer roles—since having programming skills means you can work in virtually any field.

Go Open-Source

Beyond HTML, CSS, and WordPress, Elizabeth Becker, Client Partner and Tech Recruiter at the software recruiting company PROTECH, suggests going open-source. What does that mean? Open-source software is computer software whose source code (the code that makes it work) is open to the public and the software itself is free to use. Examples of open-source software include web browsers like Firefox, operating systems like Linux, and content management systems like WordPress. Because of its collaborative and free-to-use model, Becker says that an increasing number of employers are adopting open-source software platforms, which means an increased demand for tech professionals with open-source skills. The open-source model also means there's nothing preventing you from picking up these skills on your own—open-source software is free, and is often just a few clicks away via your web browser.

Becker cites knowledge of AngularJS—an open-source JavaScript-based framework (collection of common JavaScript functions) developed by Google—as an example of an in-demand open-source skill to have. "[Even] being able to include a completed training course on AngularJS on your resume [can] validate your skills, especially if you don't yet have job-related experience with it," Becker says. "I often see highly skilled open-source professionals being able to command 10-15 percent higher salaries than other professionals without open-source experience."

It's not a bad idea to start taking a look at what open-source software you're already using and spending some time getting a better understanding of how it works—in the case of Becker's example of AngularJS, you can dive deeper with resources like the AngularJS Google Group, AngularJS questions at Stack Overflow, and W3Schools' AngularJS Tutorial.

Search Engine Marketing

Search Engine Marketing (SEM) is the practice of using techniques like Search Engine Optimization (SEO) and Keyword Research (more on these below) to increase a website's visibility on search engines like Google, Bing, and Yahoo. According to Steve Pritchard, HR Consultant at mobile phone provider giffgaf, it's also a skill that can fire up your resume and lead directly to more money when negotiating for a job. "Knowledge of how to get a business' website to appear higher in Google rankings…is a…skill that every business should be keen to capitalize on. The return on investment [is] well worth [a bump in] salary," Pritchard says. How much of a bump? Pritchard estimates that applicants with a track record of a couple successful SEM campaigns could increase their salaries by as much as 15 percent.

Whether you're learning web development, breaking into digital marketing, or working as a digital designer, two of SEO's main building blocks—SEM and Keyword Research—are skills you can (and should!) start experimenting with on your own. Not only can those skills lead to the kind of salary increase Pritchard describes, but SEO is invaluable in promoting your own brand and presence online: Knowing how to maximize your projects' searchability is crucial for standing out from the pack.

Start by reading through Google's own SEO Guidelines, which should give you a jumping-off point for the next time you're reworking your personal or business website. You can incorporate some SEO best practices easy with small tweaks like creating user-friendly URLs to make a website more searchable (for instance, "www.yourkillerwebsite.com/tips-for-up skilling" instead of "www.yourkillerwebsite.com/qs?/3600") and integrating responsive/mobile-friendly design (Google uses mobile-friendliness as part of its site ranking system). Next, dive into online resources like Moz's Beginner's Guide to SEO, and Webmaster World (an online forum for SEO talk).

Researching web search keywords that can drive traffic to your site or project is another crucial element of SEM—by getting a handle on the keyword demand for your website you'll not only get a better idea of what keywords to incorporate in your site's searchable text and content, you'll also piece together a picture of what your site's potential visitors are looking for. You can try using a tool like Google AdWords Planner (a free program that requires an AdWords account, but doesn't require you to actually create an ad) to research information on the volume of searches your keywords produce and decide which ones should be used prominently on your site.

As you read about, practice, and get a handle on these SEM skills, you'll eventually be able to add SEM literacy to your resume, and—regardless of whether you're looking to work as a web designer or a web developer—boost your value to potential clients and employers.

Microsoft Excel and Microsoft Word (No, Seriously.)

With so much emphasis on advanced coding and design skills, it's easy to overlook basic, old-fashioned computer know-how. While having these skills might seem like a no-brainer, Dawn D. Boyer, Ph.D. and CEO at Boyer Consulting, says otherwise.

"I can't tell you how many high school students in their first year of college taking my IT courses have never opened an Excel spreadsheet," Boyer says. For Boyer, this creates a disconnect when it comes to the practical reality of making things more efficient and easier in the working world. Similarly, Boyer says that database management is another overlooked computing skill that goes a long way in business.

According Boyer, Microsoft Word is the most important office software program to learn, followed by Excel. "Everyone has to write something in their work," Boyer says, "and if you have the ability to use Word paragraph and tabs formatting, as well as spell check, grammar and punctuation check, you are halfway to being more proficient in the software than about 80 percent of the competition for a job. [You'd be surprised] how many…Ph.D. students can't format a document for margins, paragraph indents, and tabs, or even insert a table, [yet] are out on the job market." As for Excel, Boyer says that vital functions to have a handle on are vertical lookup—a function used to lookup and retrieve data from specific columns in a table—and knowing how to create formulas—expressions that calculate the value of a spreadsheet cell.

If you're feeling particularly lost when trying to find your way around routine office software, consider taking an online class to get yourself up to speed. Excel, Access, Powerpoint, and Word might not be as exotic as Ruby on Rails, but they're a solid bump up in well-rounded resume skills. Boyer says that it's difficult to cite specific salary increases due to the amount of other factors involved (education, years of experience, overall skill set, etc,), but to think of these extra skills as a vital way to get yourself to the head of the application process.

Human Resources and Leadership Experience

HR skills give you an excellent chance at getting employers to pay more, says Georgene Huang, CEO and Co-Founder at Fairygodboss, from hiring to leading teams.

According to Huang, management experience is a crucial skill to leverage on a resume. The larger and more diverse teams you've managed, the higher the chance you have at commanding extra pay. Whether it's heading a team of developers, or managing a team of sous chefs, the same basic principles of leadership apply.

Specific experience with hiring, firing, and navigating difficult situations (company pivots, large scale business model changes, or moving from old business systems to building new ones) also builds a strong case for a higher starting salary. Again, think back and think big—it might feel like you don't have this kind of experience, but when you start to drill down you might be surprised at what's applicable. That time you chaired your kids' school's PTO board, helped overhaul the yearly fundraising programs, and participated in revamping the music program? It counts!

Finally, Huang says that abilities that demonstrate leadership like communication and presentation skills can go a long way in upping your value. And if you're petrified by the thought of public speaking—don't panic! Try some mock presentations with family and friends—and if you feel like you still need some work in the public speaking department, think about taking a quick speech class at your local community college or business school. In Huang's experience, the kind of leadership, decision making, and communication skills she's described can result in a 20-30 percent higher starting salary than applicants unable to demonstrate those skills.

Speaking a Second Language

Nora Leary, Co-Founder and Head of Marketing and Business Development at marketing firm Launchway Media, says that—due to her work with an international internship company—she's always looking into the economic impacts of spoken language skills. She cited studies covered by The Economist that demonstrate knowing a second spoken language correlates to about 2 percent more in annual income—which may not sound like much, until you start to crunch the numbers. The Economist extrapolates that even a 2 percent bump on a $45,000 a year salary can lead to as much as an extra $67,000 over the course of a 40-year working career, if you were to set aside your language bump in savings and figure in compound interest.

If you're looking to learn a second language, try classes at your local college, online classes, or even apps like Duolingo.

Show Me the Money

So you're an SEM wizard, you're strapped with a Rolodex of open-source certifications, you have an Excel tattoo, management skills are oozing from your pores, and you just spent the morning coding a Riverdale fan website. How exactly do you put this all together and communicate it to employers, short of an embarrassing, "show me the money" meltdown?

"A resume is the most important vessel in a job search," says Brianna Rooney, Founder and Lead Technical Recruiter at tech recruiting firm Techees. "[That] or a thorough LinkedIn." Rooney warns that an employer will be spending mere seconds looking at your resume, so it's critical you get straight to the point. List your background and skills explicitly and efficiently without a lot of filler. Remember, there's no way for potential employer to know you have these skills unless you tell therm. In Rooney's experience, a qualified resume combined with an array of bonus skills can tack on as much as $20,000-$40,000 more to a starting salary. "That is," Rooney says, "if you interview well."

So there you have it—a robust skillset presented in a crisp, comprehensive resume can be your ticket not only to landing a job, but landing it at above entry-level pay. And while there's no magic combination of skills that guarantees a dream salary, it's clear from talking to these pros that having an array of versatile skills above and beyond the bare minimum—whether it's a combination of coding tools or speaking Mandarin—goes a long way towards improving your chances for a salary that truly reflects all your hard work.