When trying to get a male and female betta to spawn, do you leave the female I'm with the male? Or do you put her in and take her out a few times to prevent them from even fighting?
Before you have them ever together, it's good to condition them first. I try to condition mine for 2 weeks before they even see each other.
Conditioning includes things like more feedings, and using various types of foods to cover all nutritional needs. Live foods are best, but not always accessible. You can use a combo of pellets and freeze dried blood worms.
Also make sure that the fish are healthy and free of any major injuries and infection/disease. Medicate/treat as needed.
Once the fish are conditioned and your breeding tank is setup and ready, place the male in the tank first. Let him get to know his new home for a little bit.
You can then put the female in something like a mason jar and place the jar in his tank. Of course make sure both fish can breathe, but be sure that the female cannot jump out so she does not get attacked by the male. Having the female visible to the male gets him excited and he will show off and flare to her and start making/adding to his bubble nest.
Once she is ready to breed with him she will start showing vertical breeding bars. She may also start flaring back. It is around this point you can add her to his tank.
It is important to supervise this process in case he does end up being too rough with her. There has been cases where the male will still kill the female. Be sure to exercise caution and use your own judgment. If now isn't the right time for them you can always try another time, another pair, or maybe switch out the male or female.
So the main point we are covering here is that the male and female need time to see each other BEFORE being able to get at each other.
Here is a link to various breeding methods. I suggest using the posted Hobbyist Method.
http://bettysplendens.com/articles/catview.imp?catid=855