Janine - the amount depends on the length and thickness of your hair (there's a booklet that has instructions when you order...there are also instructional videos on Chaz Dean's YouTube channel
http://www.youtube.com/user/wenbychazdean). My hair is about an inch past my collarbone, and on the thicker side. I started using 20 pumps (because I was so sure I wouldn't need more) but it was leaving my hair heavy and waxy, upped it to 35 and that still didn't make a difference. I thought there is no way I need more than 35 pumps, this is crazy, maybe it just doesn't work for me. So I stopped using it. Then I picked it back up a few months later and tried 40, and that was the magic number! The heavy waxy feeling dissapeared. So, yes you have to use a lot...more than you think you really need!