From Kate: What to drink

The primary thing to drink is warm or hot plain water throughout the
day. For full cleansing, this is all I recommend. However, for your
purposes, I have included the below...

As for other drinks, here's a list that goes from most favorable to
least favorable:

Warm/Hot Water
Herbal Tea
Cool temperature drink
Green Tea
Black Tea
Ice cold drink
Coffee
Alcohol

Milk is unique and often used for medicinal purposes, but varies
strongly in how & for whom it is prescribed. For that reason, I
recommend abstaining from it during these three days.