Wood or block wall construction? - block makes it simple since you can attach a conduit or box anywhere and run on the surface. Wood is not very pretty and you have to rely on the stud spacing and have the gaps between and behind the conduit.
Since you will probably have the box inside, there is only one entry to make and provide security. Once the sub is inside, it is just up to you and your needs.
You can run the conduit inside the walls and put your outlets/switches where needed or convenient. Just have appropriate breakers and wire sizes and make sure you have complete grounding, which is easy with proven steel conduit. Don't use the plastics covers for the switches and outlets, which give everything a professional look and protection.