Never put them together if you are unsure of their "moods". Only put them together when they show breeding signs. Easiest sign for Males should is nest building. While females show breeding bars (light colored vertical lines on the midsection). BOTH should swim all over the tank in an "S" style.
Keep them separated. DO NOT put in a divided tank. Flare female to female and male to male for about 15 minutes daily. Over feed them with nutritious food (mosquito larvae, daphnia, live tubifex worms, live/frozen blood worms, etc) for about 2 weeks. Within that time, they should go into breeding mode and you can put them together.
Set up the breeding tank. Put male in and float female in a jar or lamp chimney. If they flare and swim in an "S" style, you can either immediately release the female or wait 1-3 days before releasing.