If you have sex you always run the risk of getting a STD. The only way to avoid this is not having any sex. What are the other ways to keep the risk to a minimum?
Always use a condom during intercourse! Unless you know for sure your lover never had (unsafe) sex, never do it without. NEVER. With oral sex you also have to protect yourself by using a dental dam or condom.
Limit the number of partners you have sex with. Every time you have sex with another person you increase the risk of getting a STD.
If your girl- or boyfriend ever had unsafe sex in the past, you are at risk. So even if you have been going steady for a long time and your lover is monogamous you have to realise it’s not safe and you have to use condoms. Only after a STD test can you consider getting rid of the condoms (if you use another method of birth control).
Avoid anal intercourse, the most risky sex act as far as STD’s are concerned. If you have anal intercourse use a condom especially made for this activity.
Don’t share sex toys. If you do cover them with a condom.
Look beforehand at your lover’s lips, penis or vulva to see if there are any symptoms that are indicative of a STD. You can easily do this if you take a shower together before making love.