Measure and cut the stair nose to the appropriate length for the top of the stair with a miter, table or circular saw. The saw you are using to cut your laminate is ideal.
Measure and cut a piece of laminate to fit on the stair riser if you have risers and not open-backed stairs. This piece of laminate should sit flush with the subfloor of the step above it. If the laminate flooring has attached underlayment or fabric of some kind, remove it.
Install the laminate onto the riser with construction adhesive.
Install the stair nose trim onto the top step with a thick, generous bead of construction adhesive applied in a serpentine pattern and press it into place.
Attach the tongue of the first piece of laminate into the groove of the stair nose then begin installing the flooring.