I would feed excellent foods, preferably live, before introducing them. You can usually get live brine shrimp for 99 cents at most fish stores for a huge bag. Sometimes they sell live tubifex worms in little plastic bags. Feed this type of food for at least a couple of days beforehand. If you don't have access to this type of food, at least make sure you're giving them some kind of premium foods for at least a couple of days beforehand.
Keep them next to each other but not together for a few days to get them thinking about each other. You should see the female's belly getting a little fuller, and you should also see a little white spot sticking out a teeny tiny bit where her belly button would be.
If you see these things and they seem to be trying to get at each other, I would introduce them. The male will chase the female around quite a bit. They may even nip fins a little. If this is the first time either one has been mated, there will be a lot more chasing and such before they finally settle down and spawn. Have some plants, plastic or real, in their tank, and/or other places for the female to hide if the male gets a little too aggressive.
Keep an eye on them. If the male just won't leave the female alone for an hour and she is constantly running away, and has clamped fins, or if she is actually being injured, I would take her out and try again later, keeping up with the feeding schedule above and keeping them next to each other for awhile longer. Sooner or later they will mate, and this is a really cool thing to watch! Good luck to you.