Using this method (the only one that has ever made sense to me)
http://piraterodgers.com/tutorials/cbt/cbt-webpage.pdf will make me over 420" of 2 1/2" bias binding from 28" WOF. I can now make this binding in about an hour including pressing. The pictures and instructions are clear and easy to follow and there is no wasted fabric. This PDF is nine pages but if you don't want to read all of her rationale for using this method, the main instructions are on pages 4-7. Try it, you'll like it.