Getting A Betta - Have Some Questions

[BC_MoM]

Well, I have some money right now and I'm going to get a Betta.

But I'm stuck between getting a large tank, and a small one. My Grandma had a common male Betta for 4 years and she just had him in a vase with flowers. He was perfectly healthy.

From lurking around in the Betta threads, you guys seem to be against this and say they need actual tanks.

I have a couple questions..

1) What starting supplies (besides the tank and fish) do I need for my Betta?
2) Briana (Roxyluvsme13) was telling me something about floating? What is this?
3) Well.. I just basically need more information on how to get started once I bring him home!