You can nest your parts manually using a design program such as CorelDraw, where you would place all of your part close together and also rotate them to fit as tightly together as possible.
Manual nesting is free but it can take a bit of time to perform, especially if you have a large number of parts made up of different shapes and sizes
In order to nest your parts automatically you'll need to use a nesting program. There are a wide variety of nesting programs out there in both free and paid versions - and some definitely work better than others.
Auto Nesting programs can save you huge amounts of time by very quickly optimizing the layout of your parts to minimize material usage - no matter if you have 10 parts or 10,0000 parts!