5 on 2 off is a waist of time. The only reason why people do this is to stretch the kit(s) out and save money. The right way is 7 days per week. As far as how many iu's to take, You need to get your IGF-1 levels tested, a simple blood test your medical provider can do for you.
Depending on your goals and how deep your pocket's are, will determine the dose. If your planning to use Serostim your also waisting your time and money. Make sure you do your homework on the type of Hgh out there. Do a search on this board, there is a TON of great information that will help you.
Good Luck.