Wow, nothing like a long question requiring a long answer. First, before you even start you need to think about and obtain a source of food for future fry. That is the #1 failure point in betta breeding. I'd suggest looking on Aquabid, food, live for some intent green water and v-eels. You will also need brine shrimp or micro worms once the fry are big enough. The entire works should not cost over $20.
Next, condition up the breeders for a t least two weeks with live ot frozen food. I use live baby brine shrimp, but you can use frozen brine shrimp and blood worms. Make sure your female looks plump and has a white dot between the pectoral and anal fins. Once both have happened she is ready.
Take the other male out of the five gal
or a sweater box and place in the male you want to breed in with no divider. Make sure the filter creates almost no water disturbance. Place a floating object, styro cup cut lengthwise or plastic lid for the male to build a nest under. You should try to put a few objects toward the back away from the nest area for the female to hide or avoid the male. When the male makes a nest it is time to get the female.
Place the female in a glass jar filled about 1" higher than the breeder tank water level--The tank should only be 6"-8" deep. Put the jar with the female inside by the corner furthest away from the nest and leave it there for 1-2 days.
Once the male starts to chill just a little bit, release the female. Leave the jar in the tank for her to hide behind. I usually release females at 5:00-6:00 p.m. and observe several times before lights out. The male should get hyper aggressive for a while and then start running back to the nest after chasing the female. If you don't see the breed turn the lights out as normal. If you see the male get hyper aggressive or making trips to the bottom and going under the nest chances are they bred. Get the female out without messing up the nest. Don't leave the female in over 24 -28 hours.
If the male is not tending eggs-spitting invisable stuff back in the nest wait a few days and try again. Once you are sure there are eggs give him about 60 hours and you should see little lines hanging vertical under the nest. Once you see this it will only take 12-18 hours and the fry start swimming. The male will try to keep putting them back like a mad man. Once the fry are horizontal, take the males out. wait another 12-24 hours to start green water. Add just enough to make the water tinged.
If you have questions P.M. me. Good luck, it is a very cool project.