Choose the location for your fountain. Technically, you can put it anywhere, but the project will be easiest if you can select an area of the yard that is already somewhat flat.
Prepare the area by digging up any sod and setting it aside. Using the shovel, try to remove any large clumps of soil and get the area at least "eyeball" level. It doesn't have to be perfect at this point.
Pound one wooden stake into the ground at the exact center where you want to place the fountain. Take the other four stakes and do the same around the perimeter, measuring out from the center the exact distance as the radius of the fountain.
Mark the area with a can of field paint. A light square or circle will be sufficient as you will only be using it as a guide.
Shovel a layer of gravel two inches thick evenly throughout the area. Tamp down thoroughly, and then set the spirit level over the surface and extend the poles from the center to the edges of the surface where the fountain will sit. The spirit level measures slope in both directions, and you want it to be as near a perfect reading as possible.
Add a few layers of gravel to any section that the spirit level indicates is slightly lower than the rest. Tamp down, then get another reading with the level. If it is even, turn the spirit level ¼ and get another reading. Continue adding and tamping small amounts of gravel in low areas until the spirit level indicates an even surface all the way around.
Place the fountain on top of the surface, and use a regular level to briefly check the stability of the structure. Use a friend for this step so that the fountain can be set down gently, rather than drug across the gravel surface. Gently push on the fountain in all directions to check for rocking or tilting. If it is stable, fill in any bare spots around the fountain with your sod pieces. Water for two to three weeks to allow the grass roots to establish.