Vaping dehydrates you plus water will help flush your system of all the toxins. My doctor told me that majority of people are dehydrated (non-vapers). When you urinate, it should only have a slight tint. Once you reach that point, you're fully hydrated.
If plain water isn't your thing, go to the grocery store and get a low calorie water mix. I buy them from Wal-mart. Makes for better tasting water. Our water out here in KS is horrible.