For a rough and stucco-like finish, use a rough nap roller. These rollers have longer hairs. When applying the plaster, dip the roller straight into the joint compound bucket and apply to the wall. The first two attempts may not apply much, but the roller must become saturated with plaster. Once the plaster begins to stick to to the roller and wall, simply roll on the plaster.
Rollers tend to get heavy when applying thick plaster. Using 3-inch mini-rollers is a lightweight and more convenient option. Roll the plaster on the wall in all directions. For the process to move quickly, ask for an assistant to help you roll.
Some special rollers have different indentations and textures directly added onto the roller. The rollers may be made of mesh or sponge. Roll the plaster on in a vertical and horizontal patter.
Always clean your rollers several times during use, as well as all other equipment used with plaster. Plaster dries fast and can ruin your paint tools. Once the plaster is rolled on the wall, the tips of the plaster pointing up may be smoothed down with a trowel to create a softer edge to the wall. Additional methods include only rolling upward and then only smoothing downward. The roller may apply the plaster to the wall, and a drywall trowel may be used to manipulate and create additional movement to the wet plaster. Allow plaster to dry 24 hours before painting. Don't forget, if you are painting your plaster, the entire wall does not have to be covered. A 90 percent coverage rate is idea. Any bare spots will be painted with latex paint and simply resemble low plaster spots. Do not apply plaster more than 1/4 inch thick.