Hey! For a really nice fan, the best thing to do is experiment with the "pivot point" of your thumb and fingers. Practice is the key to making fans! You can read books and watch videos all day, but unless you practice, you'll never get good at it! If you're having trouble with making the fan "even", you could try applying fanning powder to the cards while you practice, but it's very important to learn to do it with a normal deck of cards. Also, make sure your deck is in pretty good shape. You can't make a fan with ANCIENT cards.
I hope what I've said helped you in some way!
PS just so everyone knows, I haven't been posting much lately due to exams at my school... LOTS OF STUDYING!!!