Measure the total rise from the lower finished surface to the upper finished surface
Determine the desired tread depth and riser height
Divide the total rise by the chosen riser height to find the number of risers
Recalculate the exact riser height by dividing total rise by the number of risers
Determine the number of treads by subtracting one from the number of risers
Calculate the total run by multiplying the number of treads by the tread depth
Select straight, sound lumber for the stringers
Mark the top of the stringer as the starting point
Use a framing square with stair gauges set to the riser height and tread depth
Align the square on the lumber and mark the first rise and run
Slide the square down and repeat the layout for each step
Mark the top and bottom cuts carefully
Cut the stringer along the marked lines with a circular saw
Finish corners with a hand saw if needed
Test-fit the stringer before using it as a template
Use the first stringer as a pattern for additional stringers
Cut all remaining stringers to match
Install stringers at the required spacing
Secure stringers to the header, landing, or deck framing
Add blocking or support as needed
Attach treads and risers after the stringers are installed
Verify all steps are level, square, and evenly spaced