Nice, making your own seeds is a great way to save some cash and make some potential fire. Only thing with bag seed is you don't know the source so watch for hermies when you start flowering out the offspring.
I have about 8 males going right now, sats, indicas, and hybrids. I've found they flower and are ready to harvest within 20-25 days, 22-23 is pretty typical/average. If you flip your males a day or two before the females (when running them in separate areas) they'll be ready when your females are ready to take pollen. If you're open pollinating you just flip them together and they'll synch up on their own, that is the male will be ready at the same time the females are. Nature knows what's what when it comes to sex, even plants
For pollinating there's a hundred ways, all you need to do is collect some of the pollen, as simple as putting a piece of parchment paper under a branch or two and tapping them (in an enclosed area of course for this method). Then take that pollen, a small artists paint brush (I buy them at the dollar store) and paint the pollen on the buds when they've hit around 3 weeks from the flip. It doesn't take a lot of pollen, and it flies around so be careful that other flowering plants that you don't want seeded are not around.