Check local building codes and permit requirements
Measure total rise from ground to landing or doorway
Determine stair width, tread depth, and riser height
Calculate the number of steps needed
Choose weather-resistant materials
Mark the stair layout on the site
Excavate and level the stair base
Install concrete footings or support pads
Cut and place stringers to match the layout
Secure stringers to the upper landing or framing
Install risers and treads
Fasten all components with exterior-rated hardware
Add handrails and guardrails as required
Seal, stain, or paint all exposed surfaces
Verify level, plumb, and secure connections
Inspect for safety and code compliance