Set up the piece of drywall to use to test the spray texture technique. Test the technique on a scrap piece of drywall before spraying the texture on a wall in your home.
Add spray texture mix and water from a garden hose to the bucket. Follow the instructions for the spray texture to obtain the correct consistency. Mix the spray texture mix and water with a paddle attachment using the power drill.
Place the spray hopper in a bucket, then pour the spray texture mixture into the hopper. Connect the spray hopper to the end of the rubber hose for the air compressor.
Position the nozzle of the hopper 10 inches to 12 inches from the piece of drywall. Press the trigger to being applying the texture compound on the drywall. Go over the piece of drywall using a back and forth motion to apply an even coat.
Allow the compound to set up on the plywood for 15 to 20 minutes. Scrape or "knockdown" the texture by using a drywall knife. Skim the knife over the surface of the compound at a 15 degree angle in a variety of directions.
Allow the texture compound to set up or dry overnight. Paint and decorate the wall after the texture has dried fully.