What can you do to prevent a sexually transmitted disease?

What can you do to prevent a sexually transmitted disease?
The surest way to prevent sexually transmitted diseases is to not have sex.

If you have sex you can reduce the chances STD if:

1. You have only one sexual partner
2. Use condoms at every sexual act
3. Choose a partner who has other sexual partners
4. Do not use needles to inject drugs and if you have sex with someone who does this