I recently taught a three day "Introduction to Hand Tool Woodworking" class here at my traditional woodworking school in Virginia, and want to share the experience to give you an idea of what the class is like. The first thing students do in this class is learn about & try out workbenches and all the different hand tools in the shop. Then they jump in and use a folding rule to measure out a length
If your shop will be attached to your house or another structure, it will likely need to match its foundation, tying the two structures together so that one does not structurally stress the other if they shift differently. That may dictate a poured concrete or concrete block foundation. Regardless of your foundation type, a cold concrete floor will sap energy away from the rest of the structure if you are not careful, so think about how to insulate it well before you build.
Unless you’re a big fan of frequent shop remodeling, planning the layout of your workshop early in its development will save you a lot of time and trouble and also can keep you from spending years in an uncomfortable, poorly organized space. And if you already work in a shop that’s as organized as a trailer park after a tornado, careful planning and a little remodeling is likely to help you make a quantum leap.