Make sure both people are consenting and want to have sex
Wash your hands and genitals first
Use a condom if you want to reduce the risk of pregnancy and STIs
Apply water-based or silicone-based lubricant to reduce friction
Have the receptive partner lie down, bend their knees, or choose a comfortable position
Guide the penis to the vaginal opening
Gently place the tip at the opening
Slowly push forward only as far as feels comfortable
Stop if there is pain, and add more lubricant if needed
Move slowly and communicate throughout
Use a new condom if switching from anal sex to vaginal sex