Call 800-herbdoc and get IF1. Follow the directions carefully. It will eventually get you going 2-3x per day and thus the amount 'per flush' will be less!
Read the schulze links above. You can move to his IF1 and IF2 Bowel Cleanse eventually.
Keep going with the water - try to get half your body weight in oz of water, ie, if you weigh 100lbs, half is 50lbs, you'd shoot for 50oz of water.