There are 3 ways to join TYW:
1. You gather a group of friends and book a yacht (the most common way). The price of the yacht is fixed and you split it between all crew members on board.
2. Grab one other friend and book a double cabin. You will then be placed on a yacht with other cabin bookers. This is a great, simple package which includes the price of a skipper, hostess and food! See here for more details about what is and isn't included.