I had a bit of the same issue. I find that if I make some Crystal Light and mix it per directions then place in a large drinking bottle and sip at it; it works. I just keep the bottle near me and just take a sip every so often. Before long, the bottle is empty and I need to refill it. I never drank Crystal Light pre-op, but found that with the flavor choices, I have been able to find some pretty good flavors. The bottle is easy to take anywhere. Mine holds 30oz. I know just drinking plain water makes it difficult to drink the required amount.