Case studies: You’ll find them on websites, business proposals, and marketing collateral. Case studies describe challenges, actions, and results (CAR) that demonstrate how a company’s service or product can achieve similar results for you.

Even dreaded infomercials use case studies. They demonstrate the products’ benefits by having actual product users tell their story. “Why, I lost 25 pounds using Therma-Trim combined with diet and exercise. Here’s my story,” says the 105-pound, athletic-looking blonde.

You can use this same strategy to promote what you can do for a company—without sounding like an infomercial—and it works.

Here’s why: This strategy helps demonstrate your expertise during—and after—an interview.

I recommend developing at least three case studies that showcase a project you led, including the challenge the company was facing, the action you took to resolve it, and most importantly the measurable result(s) you achieved. Creating one page per study is ideal.

Name your case study something enticing to an employer, such as: “Achieved a 12% Reduction in Turnover.” Include your name and contact information on each page. When writing your case study, avoid too much jargon to make it an easy read. No hyperbole, just the facts.

You could also create a web portfolio using these case studies, including links to reports or other sources as proof of concept. I recommend getting your name as a domain and creating the site using it. You can use LinkedIn to begin your online portfolio as well. Check out the Projects and Featured sections on LinkedIn, which you can use to highlight some of your best work. Be sure to adhere to your company’s social media policy when doing so.

For example, if you are a brand packaging designer, when creating your case study, provide insight on the company’s Challenge: they wanted customers to engage with brands in a new way, enabling lead capture and point-of-sale engagement. The Action steps could include assessing existing packaging and initiating the use of QR codes that drove specific consumer actions, plus creating a playbook and training department leadership for implementation.

Next, describe the quantifiable, measurable Results you achieved. What happened with the project? If you have stats that demonstrate how much sales were increased and the percentage for how much engagement improved or how many leads were generated, these are hard facts that prove you can do the job. Use numbers, dollars, or other stats that quantify and qualify your results.

You’ll be able to back up your claims during an interview with solid examples. And, for added effect, leave copies of your case studies behind for the interviewer to review at her leisure.

Show it; don’t tell it. Case studies show proof of performance to your prospective employer. A classic “try-before-you-buy” that shows you can be the solution to their business problem. And people who provide solutions get hired.

They also stay hired. Continue creating case studies and sharing results-driven stories throughout your work. They’ll help you recall results during performance evaluations and beyond, elevating your brand.

Want more help to create results-driven case studies? Check out “Rock Your Job Search,” which provides the framework and examples along with other step-by-step job search guidance.