Remove the zest of the lemon with a vegetable peeler in fat strips and toss in a bowl. Add the salt, sugar and dill and crush or "muddle" them together using a mortar or a big wooden spoon to release the oils in the lemon rind and the flavor of the dill.
Select a sheet pan with sides that will hold the fish, line it with plastic wrap and place the fish in the sheet pan. Pack the salt mixture on top of and around the salmon. Cover with plastic wrap and place another sheet pan of the same size on top of the fish. Cover a large concrete paving brick that fits in your pan with plastic wrap (to protect your pan) and place it on top of the top pan to compress the fish to press the moisture out of the fish. Refrigerate for 36 to 48 hours depending on the thickness to cure the fish. Scrape the salt mixture off the salmon and lightly rinse the fish under cool water, pat dry with paper towels. You can serve the whole gravlax at a party on a cutting board, or slice into 4 inch sections and vacuum seal and refrigerate until you need them.