My greatest " tip " is to keep it short. Like from sundown to sun up 36 hours later, or sun up to sun up for 24 hours. Short and sweet with the fasting I say. Then after the short fast, go back to raw foods that appeal to you. The raw foods will appeal to you much more after a short fast, which is the beauty of a short fast.
Do not strain either. Like if you start out on a short fast, and it just doesn't " feel right ", just drop it, and pick it back up on another day.