I've had my Scruffers (a betta) for about 6 months now. He's in a simple 1 gallon bowl, with the glass, sort of flattened marbles and a couple fake plants. I have read many places that filters can agitate bettas, and if you keep it clean, you probably won't need one.
KEY ADVICE: Check anything for the tank to make sure it won't snag his pretty fins. If it catches on hose, chances are, it'll tear his fins
I change the water once a week, if you keep him in anything smaller than 1 gal, you may need to change more often. I found these tablets called Betta Buddies (I think) at Petsmart. They come in a box of ten, plus some food pellets. After I have scrubbed the bowl, and rinsed the plants and marbles with very hot water, I just drop a tablet in, let it dissolve, rest the baggie in the water for 30 minutes, and scruffers is good to go
I also feed him twice a day, 6-7 of the betta bites in the morning, 3-4 of the Bio Gold pellets (that come with the Betta Buddies kit)in the afternoon.
You may see large amounts of bubbles floating at the top---that's a good sign. It means your fish is happy and healthy enough to mate!