Building a foundation?

Build a form around the concrete slab. Lever the edges, making sure it raises the area the half inch on the one side. Buy mortar mix -enough to cover the lower area and raise the entire area a bit for looks- mix it and pour it into the frame around the base. Take a 2 x 4 and smooth the top of the mortar by laying the board across the rectangular frame. The mortar or concrete should come to the top of the form and the 2 x 4 should slid across it smoothly for a nice finish. The board is only used to smooth the concrete and must be removed once level to allow the new elevation to dry. Once dry, remove the wooden frame or form so there will be no need for worrying about wood rot because the foundation will be concrete. Set your shed on the dry concrete and you are ready to go!!!