How to Hide Screwheads on Stair Treads and Other Wood Surfaces

A counterbore should be no deeper than half the tread's thickness. So before you start, wrap some masking tape around the brad-point bit to act as a depth indicator.

After making the counterbore, drill a pilot hole for the screw using a separate twist bit the same diameter as the screw's shank. Place the twist bit in the tapered hole made by the point of the brad-point bit; that way, the pilot hole will be exactly in the center of the counterbore.