Clean the wall of debris with a broom to prepare it for the application of the mud. Use drop cloths to cover the floor of the home if you are already living there, or leave it uncovered if it is a new construction and the finished floor material hasn’t been installed yet. Mix the mud in a container with the drill according to the manufacturer’s instructions.
Transfer some mud to the wall for spreading. Use the trowel to scoop mud out of the bucket and into your hand-held mud box. Move to your work area and use the trowel to transfer some mud out of your box onto the wall. A softball size portion of mud is sufficient and you can push it around with the flat metal trowel until it has coated the entire length of the trowel.
Spread the mud upwards and outwards from your original point of contact with the wall. Work your way from the bottom of the floor up to the ceiling for the best results. Apply the mud as thick as you like for personal preference, although you should avoid building up more than 1/4-inch thick or there will be cracking issues. Experiment with different trowel angles to achieve the finished look you want.