Combine the drywall mic with water into a 5-gallon bucket, according to the instructions on the drywall package. Insert a mud paddle into your drill and mix the the ingredients until the drywall mud is smooth.
Open the top of the pre-mixed drywall mud and scoop out 6 cups of mud, if you are using the pre-mixed mud.
Add 4 cups of water to the mud to the bucket, regardless of which type of mud you are using. Mix the mud again with the mud paddle and a drill. Once you mix the mud, insert a vegetable/potato masher into the mud and lift it back out slowly. The mud should be the consistency of a thick gravy.
Pour 2 cups of sand into the mud and mix, if you want a rough texture. Avoid adding paint to the mud as paint takes longer to dry when mixed with the mud. Instead, apply the mud with a broom, sponge or trowel and paint over the mud once it is dry.