The first thing to do when plastering a wall or ceiling is to remove the furniture and lay down large plastic sheets to protect the floor. Once the room has been prepared, begin by mixing the plaster in a large clean bucket.
Old plaster from a previous project should never be mixed with new plaster. Therefore, when preparing to apply the base coat to a wall or ceiling, mix only the amount of plaster intended for immediate use. Use an electric drill with an attached paddle apparatus to stir the plaster and water mixture, as this makes the process significantly easier while ensuring a smooth and creamy consistency.
Once the plaster is prepared, begin by loading plaster from the bucket onto a plastering trowel. A plastering trowel is a tool with a handle and a wide, flat blade which is used to smooth plaster onto a flat surface. When applying the plaster to the wall or ceiling with the trowel, start from the bottom and work upward, smoothing the plaster over the surface. Always hold the trowel at a slight angle to the wall. Make the first coat of plaster approximately 2 millimeters thick.
Once the base coat is applied, let the plaster sit for 5 to 20 minutes, depending on the temperature of the room. Next, while the plaster is still pliable, run the trowel over the base coat. This smooths out the plaster somewhat. A thin layer can be applied to holes or depressions in the plaster in the same manner as the base coat. Let the plaster sit again for no less than 30 minutes.
Finally, to polish the plaster, simply wet the blade of the trowel somewhat, and flick water onto the fresh plaster wall with a large paintbrush. Run the wet trowel over the surface one more time to smooth and polish the plaster wall.