A very basic plan would be to have your building drawn out on paper with the locations of your utilities in the plan. What do you want and where do you want it. If you put in a sink, then you need a drain. If you don't have septic, sink drains have been known to just dump water out in the woods to water the plants. Probably not legal, but very common.
Level the pad and be sure to include lots of drainage. When it rains, allot of water will run off the roof. More so then it ever does on the grass since none of it sinks in. All that water needs to get away from the building as fast as possible.
When the dirt work is done, set your forms, or mark your layout on the ground for your posts. If you are putting in a slab foundation, set your forms. With the forms in position, it's easy to measure where your utilities need to be. These go in next. Water, sewer and electric. Stub them up a foot or so above the height of the finished pad and cap them off with either tape or caps.
Pour the slab and start framing.
I read a book on how Habitat for Humanity builds their homes that was very simple and easy to follow. It showed all the basic steps and how to properly frame a building. It was good for beginners wanting to build a simple home, barn or shop, but it wouldn't be any good if you wanted to build a pole barn. I've seen a few pole barn books and would not recomend any of them. There is more to writing a book on how to build something then just experience building those things. A good writer or teacher is seldom a good builder, and it's true the same way around. A good builder is rarely a good author.
Eddie