How to Apply Venetian Plaster in 3 Steps

Apply at least two coats of plaster to the wall. The first coat is the base coat. It lays the foundation for the Venetian plaster and helps ensure a smooth finish. 

Open the can of Venetian plaster and give it a stir with a mixing rod. Spread a drop cloth over the floor of your work area, then put on your gloves and safety goggles. Use your putty knife to scoop up some of the plaster, then apply the plaster to the trowel. 

The side of the wall you start at depends on whether you're left- or right-handed. If you're right-handed, start on the left side of the wall and work your way to the right. If you're left-handed, start on the right side of the wall and work your way to the left. Starting on the opposite side of the wall means you'll go over the plaster as little as possible as you work. 

Hold the trowel at a 15- to 30-degree angle as you apply the plaster. Use circular motions to create texture on the wall. The smaller your trowel strokes, the more textured the wall will be. Use larger strokes if you want a smoother surface. 

Don't worry about making the first coat perfect—some gaps in the plaster is ok and may be preferable. Also, don't overwork the plaster at this stage. You don't want to polish it to a shiny finish on the first coat. 

Clean the trowel as you work, removing excess plaster from it. 

Once the base coat is applied, allow it to dry for about six hours. As it dries, the plaster will become lighter. If there are any large lumps or bumps after it's dried, you can gently knock those off with a putty knife or smooth them down with sandpaper.

Next, apply the second coat of plaster. Put the plaster on the trowel, and holding it at a 60-degree angle, apply the plaster to the wall. Start on the opposite side of the wall from where you began the base coat (right side if you're right-handed, left side if you're left-handed).

This time, use large strokes to apply the plaster. You want plenty of overlap. Smooth the surface as you work.

Burnishing the plaster gives it a shine and removes any irregularities or rough patches. Start the burnishing process before the second coat has fully dried. You can either burnish as you go, apply plaster to a small section of the wall, then burnish it, or wait until the entire wall is coated with a second coat, then burnish. 

Use a clean trowel or very fine grit (at least 400-grit) sandpaper to burnish. Start on the same wall side as you began the second coat. If you're using a trowel, hold it at an angle and use moderate pressure as you rub the surface. The friction from the trowel will remove any bumps. 

If you're using sandpaper, use circular motions as you rub the paper across the plaster. 

As you work, run your hands across the plaster to assess how smooth it is. If it feels rough, continue to burnish. Once the plaster is your desired smoothness, use a damp rag to wipe away any dust.

A wax top coat seals your Venetian plaster wall and protects it from moisture. A sealed wall is also much easier to clean. You can skip this last step, though, if you prefer, and if you're working on a wall in a room without a lot of humidity. In the kitchen or bathroom, a wax top coat is a must-have, though.

Let the plaster dry for about 48 hours. Pour the wax top coat onto a sponge, then use the sponge to apply the top coat to the wall. Use circular motions to put the wax on the wall, apply two or three thin layers.