As weird as it may seem, PRACTICE.
During the spring, I get up an hour earlier than normal and increase it over the next few weeks. By summer time I am functioning on 4-5 hours sleep without a hitch. Come Fall 24 hours is not hard to do at all.
A word of warning, sleep deprevation takes time of your life span....but the way I figure it is you'll have plenty of time to sleep when your dead.
