Mine bred shortly after I got them, and then never did again. I kept some of the eggs though, and managed to grow a few young ones. Here's what I found.
These are egg scatterers, and when they spawn the eggs go everywhere, but most down to the gravel (they don't stick to anything); if you have a magnifying glass, look around the edge of the tank at the top of the gravel for eggs. After a day or two, the eggs will hatch into tiny, splinter-like fry, which hang out on the glass for some time, then start moving in small jumps. As they move around like this they often get eaten. So if you have a tank pump or siphon (I used a turkey baster which is only for fish use), suck up the eggs or the hatched fry along the edge where the gravel meets the glass; in a pinch you might use a net if it's all you have. Deposit them in another small tank with some tank water from the big one (water should be slow-moving if at all, these fry WILL get sucked up by a tank filter).
After that it's a matter of feeding them. I had OK luck with the Hikari First Bites stuff, but the fry tank I was using had some greenish water which probably had other 'food' in it.