Check out the Queer and Trans Safer Sex Project for a bunch of zines dedicated to safer sex!
It’s good to know about blood-transmitted STIs and communicate with partners about safe sex whether or not you have an STI. Check out this chart on common symptoms, testing and treatment, but remember that the most common symptom for STIs is no symptom at all, so it’s important to get regularly checked for STIs if you are sexually active. There are national organizations like Planned Parenthood as well as (often free) local resources for this!
It’s important to understand how to keep sex pleasurable and safe while on drugs. This website is specifically about crystal meth, but has good tips that apply to drug use in general, including clean needles, planning ahead, and setting boundaries.