1. Get a pizza box
2. Put a modest-sized hole in the pizza box
3. Drive to her home
4. Insert peen in the pizza box
5. Knock on door
6. Wait for the other guy inside to finish up
7. Have her open the pizza box when she finally gets to the door
Back-up Plan: If in the really off-chance that she's creeped out by the whole ordeal, have an engagement ring ready to buy her silence.