Here are three tried and true methods for preparing cake pans.  They all work.  The best one is the one that works for you.

Method One:  Spray bottom and sides of cake pans with non stick spray.  This is the easiest of the methods.

Method Two:  Coat the bottom and sides of pans evenly with butter or oil.  Dust the oiled pans with all-purpose flower.

Method Three:  Spray the sides of the pans with non stick spray.  Cut Bakers’ Parchment to fit the bottom of the pans.  This is the most sure fire of the methods and my favorite.  To make the parchment stay in place on the bottom of the pan you may need to put a small smear of butter or margarine.  You can also line the sides of the pan with parchment, however, depending on the pan, this can be tedious.