1st Time sex. Relax; best that your first partner is experienced, well-versed and patient.
Consult gynecologist. An initial check up is a good idea. Consultation will also include use of contraceptives including birth control medications, hpv vaccine is very strongly recommended. Chose a loving partner with whom to share what hopefully will be a wonderful experience. Chose a pleasant, clean, private, comfortable and hopefully romantic setting. Good luck.