Sure! Basically the pre fast consists of 3 days where you progressively lower your food intake to teach your body to function with less food. Also, it helps you not get as hungry because you are getting used to less food slowly.. During this prefast you also are trying to find out how many Digestive Stimulator pills you personally need to have at least 3 BMs a day. As you read in my post, I was severely constipated so I have been using alot but there are suggestions on how many you might need in the instructional booklet you'll get. You can take them at night or even during the day whichever works best for you. This prepares you for the actual fasting because when you fast it is important to keep your bowels moving alot to get rid of the waste and toxins and on a liquid fast, I guess the bowels can tend to slow down. It is really a great cleanse! I hope this helps and if you have any more questions just ask! :)