To build a shed door, choose the size of the shed door, and then select the appropriate size of siding sheets. Find a flat, even surface. Lay the siding down so the sheets overlap each other slightly similar to when the shed doors are closed. Where the siding overlaps, whittle the edges down so that the siding comes together to create a single flat surface. Attach hinges to the opposite ends of the shed doors. Panel the doors as desired.
Attach hinges with screws and a drill. Pre-drill and pre-screw the siding to protect it from splintering or cracking. Screw the hinges into place on either the outside or inside of the door as desired. Install hinge boards, and screw the opposite end of the hinge onto the same side of the board as the siding. Hinge boards should be slightly taller than the door itself. To avoid metal corrosion, use galvanized screws and hinges.
The door should be set 1/4 inch away from the hinge boards when in the open position before installing both sides of the hinge. This space allows the door to swing open and closed easily while staying flush to the boards when closed. Install the hinge boards on the interior or exterior of the shed depending on where the hinges were placed on the boards and doors.
If desired, panel the siding with boards, and finish with a stain, veneer or paint.