- 1). Lean your 2-by-4s that are 8 feet long against a wall. The angle you place them should be the angle you want to make your ladder. Lean them 3 feet away from the wall.
- 2). Use a level and pencil to mark the bottom and top of each 2-by-4 where it needs to be cut to make it horizontal to the ground. Use a saw to cut the wood at these marks.
- 3). Mark the location of each step on the 8 foot 2-by-4s with a pencil by measuring an even distance between steps. Making each step one foot apart would be adequate. If your steps are 10inch thick, make another marking 1 inch above each initial mark that you just made.
- 4). Measure each rail at 1.5 to 2-inch intervals and mark each rail in the center at these intervals. Use a drill to make a 1/4-inch hole at each marking.
- 5). Cut four lengths 1 foot long each out of 2-by-4s, and do the same thing to these as in Step 4. Connect these pieces to the inside of the rails using bolts and wing nuts. These will act as the adjustable leveling strips so you can adjust the height of the step ladder.
- 6). Make a rabbet cut in between each 1-inch step mark you made in Step 3. Make each rabbet cut 1/4-inch to 1/2-inch deep. The ends of each of the steps will slide into these cuts.
- 7). Cut each step, making the first at least 15 inches long and decrease the size of each step by 1 inch until you reach the last step. Install the steps with screws from the outside of the rail into the step.
- 8). Cut a top for the step ladder using the 1-by-6 timber. This should be large enough to cover the entire top of the ladder. Drill pilot holes in the end of each rail and screw in the top you just made using wood screws.
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