m0useanswered grow question 2 hours ago depends what kind of seed you want.
First bit is picking out the plants with the traits your like and you think will be good. aka selection a donor and receiver.
If its reg seed, you need a male plant and a female plant then let them "smash" and you got regular 50/50 mix male/female seeds.
If its fem seed, you need to reverse a female to make male parts, this is done with silver like CS or STS, then you use that pollen to make seeds.
Some things are a much more complicated but this is the basics of it. Timing of when you pollination and the age of the plant, how long you let the seeds mature, selfing, genetic retardation are all other issue of making seeds. Just don't make seed from seeds from seeds if you are making fem products to avoid issues down the road. F1's work good for giving the plant more vgiour.