A friend of mine asked me to describe the bases of sex. Well... we all know I am ALL for this, so here it is.
Quick, simple, and to the point.
1st - Kissing. Hopefully with a bit of tongue, nibbling, sucking (on the mouth - get your mind out of the gutter... for a second), etc. A good make-out session could suffice as long as his mouth stays above the shoulders.
2nd - Kissing and touching of the breasts or other erogenous areas of your body. The breasts can be done outside or inside the shirt, but other areas must be fully clothed for this to count as second base and not sliding into third!
3rd - Stroking, rubbing, or oral stimulation of the lady bits (or man parts). Your kissing has definitely escalated past the head... all I'm saying.
4th (HOME RUN) - Do I really need to say it? As Jim Carrey would say, "You stuffed her like a Thanksgiving turkey!". Full on penetration. Sexual Intercourse. Doing the nasty. Banging. Whatever you want to call it... it's done. You are officially a score on the board! Hence the term "you scored!"
Hope that helps. I'm here for your every need. (No touching though. I don't touch strangers. HAHA).