I'm trying to grow tomatoes in a pot (one plant per large pot). How
often should they be watered and how much water should they get? I also
don't know if I should use some sort of drip irrigation system
(something simple like soda bottles) or just water them by hand with a
watering can. How often should I use plant food?

I have what I call a thumb of death. I cannot grow plants at all. In
fact, I can't even grow potted grass for my indoor cats. So obviously,
I need some help. On the bright side, my tomato plants haven't died,
yet.