Haha, I'm a little crazy. I form a committee each year to do it with me (aka like 2-3 friends/roommates), pick a theme at the latest, about 6 months out. Plan for 4 and then build and prepare for 2. My invitations are also entirely different each year and little puzzles to the theme for the year. Each year about 1-4 people guess the theme in advance. They're not easy and super misleading, ha.