Just do a search for bettas on MFK. Lots of good advice.
Here is some advice I posted:
Live foods are not necessary to raise betta fry. You can feed newly hatched fry boiled egg yolk squeezed through a fine mesh (like a stocking).
Breeding bettas: Condition female until belly is nice and plump. Male should be in breeding tank. Water should be 6"-8" deep, 78 - 80 degrees. Tank should be covered to keep the air inside the tank warm. Breeding tank should contain plants or some floating styrofoam for male to build bubble nest. Put female in glass container and place in breeding tank. Once male has built bubble nest, release female. Fish should spawn within hours. After spawning remove female. Male will take care of eggs in nest. Reduce water level by a few inches to make his job easier (eggs fall to bottom and male puts them back in nest). Once fry hatch remove male. You can then begin to feed them egg yolk. Remember to keep the air above the water warm. Hope this helps.