Measure the length of the flange bolts that are on either side of the floor drain and the depth of the toilet bolt holes. If you need more length, exchange the flange bolts with longer ones from the extension kit.
Tip the toilet on its side and, with gloves on your hands, gently insert the wax ring into the bottom drain hole of the toilet. Take care not to move the wax out of form, and don't get it on your skin or clothing.
Raise the toilet enough to get your arms around the sides and lift it, being careful not to bump the wax on the floor or walls.
Insert the toilet onto the floor drain hole, aligning the bolts on the floor flange with the slots on the sides of the toilet. Lower it straight down so that the wax seal doesn't hit the edge of the drain and bend out of form.
Close the lid and sit on the toilet to seat the wax ring firmly into the drain opening, being careful not to wobble from side to side.
Tighten the nuts onto the flange bolts, being careful not to overtighten. This could crack the porcelain and ruin the toilet.
Attach the water supply line to the toilet and to the water supply above the shutoff valve. Wrap the threads with pipe-thread tape and use an adjustable wrench to tighten it securely.