Just ask your doctor what he or she suggests.
It is good you are doing this.
Common tests are HIV, hepatitis, syphillis via blood draw.
For men, I believe a urethral swab is done for chlamydia and gonorrhea.
Herpes is a tough one because a lot of people are positive for the antibodies in the blood, which doesn't mean you have the active disease. Ask your doc about this one.