To add to what Koorbloh said;
Hang on to your poker 'card' even if you aren't playing the game. They use it to stop people from poaching the course.
There are three events (family, ironman, ds), you sign up for only one of them. The course for each starts in the same place. The course on the private land is completely marked. Everyone goes the same way until the course splits into Ironman and Family routes. If you're doing the DS ride, take whichever route you prefer. If you're not doing the DS ride, just keep following the markings. If you are riding the DS, at some point you'll get back to the camp and then start following the directions in the roll chart for the public road section.
It's not necessary -but really nice- if someone in your group has a roll chart holder.