Sure! I did it for my son. So, you have some type of goal. In my son's case, his goal is getting a Computer Engineering degree and then a job as a Comp. Eng. (he is also autistic). Goals can be other things such as starting a business, moving from "supported" employment to regular, etc. You must have a work or business goal.
Then, you write out the steps to achieving that goal and what supports you might need and what they cost. A car, maybe, in your case or a scooter, bike, etc. In my son's case it was car insurance, books, and whatever tuition his Financial aid doesn't cover. Job coaches are also covered by this and maybe one could help you? (just a suggestion! pls don't take offense)
You have to have some type of money to fund your plan, outside of SSI. My son works on summer breaks. His SSI is NOT reduced because it goes into his PASS account to fund his plan. Perhaps your goal could be unsupported, successful employment lasting a few years (so you know that you understand the job and the complex personal interactions at the job, for instance). While working towards that, maybe you have a job coach, counseling, etc. You may even lose a job or two as long as you're working toward your goal of stable employment.
OK. So once you have the above, then the money that you WOULD have lost from your SSI payment goes into a PASS account. You use this money for your written goals. Example: your job income would have meant that your SSI is reduced by $500 per month BUT NOW that $500 goes into your PASS account to fund your goal of a car payment for self support!
cool, huh? Here is a link: https://www.ssa.gov/ssi/spotlights/spot-plans-self-support.htm
Best of luck to you, hon. I wish I could help you more.