Use a rake to go over the gravel surface of the pad, evening out the surface by lowering high areas and filling voids. Add additional gravel to fill depressions in the surface if necessary. Pour the gravel into the depressed area then smooth it out with the rake.
Level the pad by placing a 4-inch by 4-inch plank over the pad frame on opposite edges. Drag the form over the frame edge, using a back and forth motion to shift the gravel in front of the bar, leveling the surface in the process.
Wet the gravel pad with a water hose, dampening the gravel without saturating it. Tamp the gravel down, using a heavy object to compress the gravel. If the compressed gravel falls lower than the frame edges, add more gravel and repeat the smoothing/leveling process. Tamp again until the compressed surface is even with the top of the frame.