Betas

The male will make a bubblenest.
I would suggest a tank instead of bowls
Be sure to remove the female right after. One will shred the other.

Kim

A 10g tank will work nicely. Leave it barebottomed, and put in a devider so the pair can see each other. Feed them with a variety of live and frozen foods to condition them. Lower the water level and put on a glass cover so that the young's labyrinth organs can develop properly. Introduce them when he's made a big nest and she's nice and plump, and like Puff said, remove her afterwards. You need to have a supply of really tiny food ready for when they absorb their yolk sacs. You also need to have something to put the young males in when they start flaring at each other. I'd recommend looking through google and finding some good sites for more info, but that's the basics.

The black splotches are probably just par of her colouring and won't go away. Most pet store bettas are not a very good quality...

I wouldn't recommend breeding them at all unless you're really serious and commited to the project. Don't forget that within a couple of months you'll be having to separate all the male fry or they will start killing each other. What if you are lucky enough to end up with 50 male fry still alive by that time? Are you prepared to clean 50 betta jars daily until you figure out what to do with them?

Hope that didn't come across harsh, just that I think a lot of people don't realize the chore it can be to breed bettas if you aren't prepared for it.

I agree with arky. Raising betta fry is very time consuming. And seperation is a must. You'll need to have 'jars' to hold them, which means a lot of space. If you are aware of this then the what you need to look for are the following.
1. First make sure the male and female are about the same size. If one is larger then the other they may end up killing each other. If the female is larger then the male, he won't be able to wrap around her.
2. You have to make sure that she's ready to breed. If you start too early and she's not ready you may end up scarring her for life. She may not breed with another male ever again.
3. Conditioning is critical, if they're unprepared they will end up exhausted before they do anything, or die. He should be building his nest readily whether or not he's with a female. She should have a huge 'chest' meaning she's loaded with eggs.
4. You have to make sure she is willing to breed with him. She'll show vertical bars if she is willing when you let them see each other.
5. Make sure you observe them closely when they're in the tank together.

This is just a rough outline of what you need to make sure of before you start breeding. Make sure you look up more information on the net before you do anything as stated, it is a huge responsability.

First, you need to do a lot of research on the subject before you think about it. Another thing is that bowls that can't be heated and filtered are inappropriate housing for bettas. IMO, optimum tank sizes for a sole betta are 2.5-10g tanks *with* heaters and filters.

I, like the others, urge you do reconcider breeding bettas. It takes a lot of time and patiences and there is more too breeding them than just sticking the male and female together... it can sometimes take up to a month for both fish to be ready to breed. Then, it takes another two months to get the fry to a sellable size and you'll need 100+ jars to seperate the males into... in those jars you'll need to do daily water changes. On top of all this, you'll have to find someplace to take them. You probably will not be able to sell them, just give them away. Fish stores get bettas dirt cheep and will only be willing to buy them from you, at most, what it costs them to get them from the suppliers... so you'll be looking at *maybe* 40 cents each... So, suppose you get 50 fry to a sellable size you'll maybe get $20 (credit not cash) at the store. But, then you have to subtract food costs, housing costs, electrical costs, and you're time.. by the time you're all said and done... you'll be lucky if you make any profit at all or at least don't lose any money.

So, unless you have hours a day to spend with these fish and the money to properly house 50 or more fry (assume 25 males = 25 seperate 1quart jars that need cleaning every day) and the time to spend on a good amount of research; breeding and raising these wonderful fish properly isn't feesable.

If you'd just really like to breed some fish for fun, the easiest and cheapest fish to breed are livebearers. Guppies and endlers (if you can find pure ones) are probably the easiest since they are so small and don't require more than a couple of 10 gallon tanks and a little research to get started casually breeding them.