One product I like to use is Wilton's Bake Easy spray. All you do is spray it in your pan before you put your cake batter in. When you cake is done it will come out of the pan very easily with few crumbs.
Treating your pan is the first step to successfully getting your cake out, but the second step is just as important. After you take your cake out of the oven, only leave it in the pan to cool for 10 minutes, and not a minute longer. After it has cooled for 10 minutes you can remove it from the pan and let it continue cooling completely.
These tips should help you in becoming a successful cake decorator. Happy Baking!