What is the best method for accessibility on a page?

I’m currently building a website and have decided to keep it really bare bones. I’m just giving it one color and a few shades. My only concern is that users with visual problems with have issues when viewing due to the low contrast. I don’t have that issue, so I can’t test it on myself, and it feels weird asking for people with vision problems. That being said, if anyone has any tips for building with that problem in mind, please let me know of some tips/advice. My site is 100% free so this is not a promo by any means(this is a side project for fun). Im only linking it so people can see what I mean: freeversion.info