one off moulds for custom small parts

Hello everyone, very new to the forum not really new to laminating. I've been out the game for a couple years but I've got an idea stuck in my head about making custom one off small parts for people in my local area. The lay-up of the products is fine, done it more times than I care to remember the thing I'm stuck on is what will be the most effective way of making the moulds, desperately in need of someone to bounce ideas off. Thank you