Do you have to pay any money to sell on CafePress? Please give a simple answer.?

I recently got a store on YouTube and I would like to sell merchandise and T-shirts and things on CafePress, but, I don't know if it costs. Please answer in the simplest form possible. I'm not too good with sales and things. Thanks!
Btw my YouTube is: www.youtube.com/user/ShardGaming

They take a percentage out of all the merchandise that they sell for you.