Polishing plaster helps bring out the various shades and textures of the plaster finish. Burnishing plaster does provide a shine to it. Waxing the plaster polishes it and protects it from accidental burnishing created when hard surfaces brush up against furniture, toys or shoes. You can burnish or wax your plaster, or do both.
Sand a steel trowel with a fine sandpaper. This removes any imperfections and burrs.
Wipe the trowel with a tack cloth.
Lay the trowel against the plaster so it's nearly flat and pull it across the plaster in firm, short strokes. Add as much polish as you like on the plaster, using this burnishing technique.
Wipe down the wall with a tack cloth.
Wax the wall with a thin coat of plaster wax. Rub plaster wax into the wall in small circular motions, covering the entire wall.
Once you start burnishing the wall, don't stop in the middle. Complete the full wall to avoid variances in the way it looks. Stopping in the middle and starting again the next day often results in different pressures and angles being used, which changes the way the appearance. Note that waxing your plaster may make it more difficult to paint over it at a later date. The wax sometimes makes it difficult to achieve even coverage.