Remove the doors, knobs and all hardware from the cabinets. Spread tarps over the floor and put painter’s tape around the points on the wall where the cabinet is mounted.
Sand the cabinet by hand with fine sandpaper. Don’t try to sand off the existing finish completely but just enough so that the surface is dull, clean and flat. Wipe off the dust.
Mix one part paint with one part glaze in a bowl; this will give a medium antique look. For a lighter look, add more glaze; for a darker one, add more paint. Brush the glaze mixture over one span of the cabinet, applying it thickly. Cover the span completely. Let the glaze sit for two or three minutes, just until the shine starts to fade from the surface, indicating that it’s starting to dry.
Work the glaze into the look you want. One option is to wipe away part of the glaze, haphazardly, with a dry cloth, leaving some of it gathered in crevices and corners, giving the piece an antique look. You can create a "distressed" look by scraping lightly over the glaze with car keys or other hard objects, leaving lines and score marks. Or you can press and pull a natural sponge over the whole surface, giving it a mottled look.
Continue applying glaze to the entire cabinet. Once you get the look you want, let it set overnight.
Spray on three coats of polyurethane. Sand lightly between coats, so the next coat will stick. Let the polyurethane dry for 24 hours before reassembling the cabinets.