Measure and cut the riser to the length desired using the 16-foot steel measuring tape and circular saw. The riser is attached vertically to the stringer and is underneath the step.
Attach the riser to the stringer using three 2 1/2-inch trim head decking screws on each side. Ensure the riser is in the vertical positon before attaching with screws.
Continue this procedure for all risers.
Measure and cut the steps to the length desired using the 16-foot steel measuring tape and circular saw. The step is the top surface that will be walked on.
Leave around 1/8 inch between boards for each step, and screw each one down with the portable drill. Use three 2 1/2--inch trim head decking screws on each step. The trim head decking screws used for the risers are appropriate for the steps too. You can use wood putty to cover the screws to provide a more professional look.
Leave 1 ½-inch overhang on the steps to give them a better appearance.
Repeat Step 3 and Step 4 until all steps are installed.