He'll need a filter unless you're willing to do very frequent water changes. Bettas like variety in their food, so I feed mine brine shrimp, bloodworms, and pellets. I find they take the pellets better if they're softened in water as well. Make sure you have supplies to test water quality and temp. The rest is kind of up to your taste. Also, just make sure any decorations aren't sharp. If it's rough enough that pantyhose would get caught and tear on it, it's too sharp for a betta's fins. And if your tank is smaller than 5-gal, be careful that the heater doesn't overheat your water.