Make as many friends and contacts as you can, take advantage of every opportunity to meet new people.
There's no need for you to feel ashamed of your sexual history, sex is a big part of most people's lives.
Even if you regret meeting some of the guys, there's still a world of difference between ons and being a vicious criminal.
I'm assuming that you have an interesting personality, reasonable social skills and looks that don't scare guys away.
Focus on the sort of guys you want to get into a relationship with and decide what your non-negotiable are: age range, physical type, employment, hobbies.
Then think of at least two things you want to avoid under all circumstances.
For example- I only date guys at least 15 years older than me and try to avoid anyone who keeps a snake or meerkat as a pet.