Minimize the number of people you have sex with . Don't mix sex with drugs or alcohol - you are more likely to make bad decisions about sex when you're drunk or high. If you use sex toys, don't share them without disinfecting them first. Condoms , female condoms , dental dams . Condoms catch the sperm and other fluids that are released during sex.
Condoms provide very good protection against STDs.
You should use them every time you have sex - for vaginal or anal sex and for oral sex on a man. Even though this is possible, condoms provide A LOT of protection . The key thing is that condoms do not allow the mixing of the fluids. This is what helps prevent the spread of disease. It's also makes sex a lot less messy, which can be good.