Does anyone know how to do erp for yourself? How should I start?

How do people start practicing erp on their own? Because I tried yesterday, and it helped for like two hours, but it always comes back and scares me. I don’t think i can practice it the right way without help.

How long should I do ERP, so that my brain gets used to it, not to say tired?! I've been working for about three months, but everything still seems vivid in my head, there are even vulgar words in detail... since the sexual topic is both a groinal and a feeling that I want to touch myself. It's mostly related to faces and genitals, so how exactly can that go, if it's emphasized that sex pictures in themselves give that feeling, whoever is in them?

What would I do for ERP if my OCD says because I didn’t do something correctly or remember something I will have panic attacks that don’t end?