Don't fret UnderanOpenSky - my kids and I laid a 400square foot base for the field kitchen in the wood using 2 tons of sand and 120 old slabs off gumtree. We did it in a weekend. Remove the grass, stomp the earth, lay sand and level with a long straight edge, more stomping (ideally a whackerplate would have been nice but we just stood on scaff boards.We only had a 2inch sand layer but the earth was nicely compacted...and even the shed will only need a subbase of hardcore and 3inches of sharp sand before popping slabs on top. I hardly ever lay slabs on anything but sand and maybe point in the joints with some brush-in dry sealant. Oh, forgot to mention the most important buit which was setting the timber edging - I used 4x1 tanalised timber - this also acts as the level for the straight edge.