Firstly, before breeding betta you have to place both male and female's tank close to each other for at least 5 days...during that time you also have to give them food enough, fresh food is the best.
After that 5 days, then you just put them together in breeding tank. Wait for 1-2 days you should see the bubble nest...if the male didn't build bubble nest , I think that male can't breed ---> I mean even if you try your best, he just can't breed.
Guppy and betta fish
is the most stunning fish for me.