Sand out the inside of each dent using your 200-grit sandpaper. Fold the sandpaper into a triangle, if necessary, to get the edge of the paper into the dents. Get the interior of the dents free of shine. Blow off the dust.
Use your thumb to press wood putty into the first dent, packing it down tightly and letting it mound up a little on top of the surface. Repeat for each dent.
Flatten the putty by pushing your putty knife forward through it, "cutting" it off at the level of the floor. Repeat for each dent.
Let the putty dry eight hours. Lightly sand the surface with the sandpaper to smooth it out. Wipe up the dust.
Dab polyurethane over the area of the putty, using a small paintbrush. Let it dry for six hours.
Lightly sand the new gloss to slightly dull it. Add on a second layer of polyurethane. Let it dry 12 hours.
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