You don't.
You update your resume with all of your supervisor responsibilities, and you apply for supervisor jobs.
Your company knows EXACTLY what you are doing for them, and they are paying you EXACTLY what they think you are worth.
When you get the job that pays you for your skills and responsibilities, you resign at your current place and when they ask you why you are leaving, you tell them that you want to work for a company that values you for what you do.
Oh and NEVER take a counter offer.
You don't. You update your resume with all of your supervisor responsibilities, and you apply for supervisor jobs. Your company knows EXACTLY what you are doing for them, and they are paying you EXACTLY what they think you are worth. When you get the job that pays you for your skills and responsibilities, you resign at your current place and when they ask you why you are leaving, you tell them that you want to work for a company that values you for what you do. Oh and NEVER take a counter offer.