In permaculture we try to let nature take its course when it comes to reproducing our plants. Hopefully, if we design with sufficient biodiversity natural pollinators like insects and birds will do the job for us and ensure a bountiful garden in successive years.
But sometimes nature needs a helping hand. This guide from the University of Illinois gives an in-depth look at how pants reproduce and offers guidance on how you can pollinate and breed plants from your own garden. There are even specific experiments with corn, squash and tomatoes for you to try your hand at.