Most rivers in the west have a permit lottery. You apply for several dates (1st, 2nd, 3rd choices) and pay a small application fee (10-15 bucks). One permit application per person. Most applications are due in Jan or Feb. Winners announced by March. Your permit is only good for a specific launch date and specific days on the river. If you win a permit you then provide additional details (group size, assigned camp sites etc) and pay a more expensive group fee based on the number of folks.
The permit holder does not need any particular river experience, however your trip leader needs to have the experience and skills to navigate the river. The permit holder must be on the trip and the permit in not transferable. If you cannot use the permit you can turn it back in, however a no-show is banned for the following year.
Lots of web sites with easy links to permit info.....
rivergeek western river permits
Note: the permit holder is responsible for seeing the entire group is following the river regulations. With more responsibility you will need/want more safety gear...
Get familiar with the reg's on the various rivers and be prepared. Most rivers will require a toilet system, fire pan, fire blanket and major medical kit. Also labeled
PFD's, required spares for each boat over 16'. You might also want to consider a Z-drag kit and a satellite phone (you can rent them)
Get a copy of the book 'River Otter' www.anotterpress.com
This is a great guide for trip planning including things like 'how much propane do I need for a 5 day tip?