Remove any window and door trim that has been applied over the surface of the asphalt sheet siding. Do this carefully with a crowbar, and mark the pieces of trim so you know where they came from and can put them back more easily.
Pull the asphalt sheet siding off the wall of the house beginning under the eaves. The siding will have been installed so that the lower edge of sheets that are higher on the wall overlap the upper edge of the lower sheets. Beginning at the top makes removal neater and easier.
Go over the wall with a claw hammer or a small crowbar and remove any remaining roofing nails. When you pull the asphalt sheets off, some of the nails will go with the siding and other nails will pull through the siding and remain in the wall.