Hi Ducky...
Okay as far as a drink, one or two should be fine but don't have them on the same day that you take your MTX!!! I made that mistake but only once! and the next day I was sick sick sick!!!! On many occasions I have had one drink the night before my MTX dose and it has never been an issue as far as side effects or with my labs coming back strange.
The folic acid is over the counter in the vitamin section and I take two each night including the day I take my MTX, and if it isn't enough to counteract the MTX, you can get a script for the Leucovorin from your doctor and that is taken with 24 hours of your MTX dose, I have taken that the day after, and when I do that I don't take the folic acid.
Someone also mentioned water? Please drink a ton of it! I have noticed that when I don't I get a burning sensation in my hips.
Good luck to you!