Measure the stair run, rise, and wall height
Check local building code requirements for handrail height and placement
Mark the handrail height along the stairs
Locate wall studs or solid mounting points
Cut the handrail to the needed length
Mark bracket locations on the wall
Drill pilot holes at the marked bracket locations
Attach the brackets securely to studs or anchors
Position the handrail on the brackets
Fasten the handrail to the brackets
Check that the handrail is level, secure, and continuous
Sand any rough edges and finish the handrail if needed
Test the handrail by applying firm pressure before use