Any advice or tips for care of the Siamese Fighting Fish, also known as a betta fish?

Someone just gave my daughter a Siamese Fighting Fish, also known as a betta. I am an animal lover, and so i would like to take good care of the little guy, and not have him suffer needlessly. In addition, I would not like a dead fish to have to deal with replacing him with a similar one so as not to have an upset 3 year old.

Any tips or advice on the care of this fish?