Open your container of joint compound and pour its contents into an empty 5 gallon bucket.
Measure out a cup of fresh water and pour it into the bucket. For a thinner, more workable mixture, another cup of water may be added later.
Attach the mixing paddle, also known as a mud paddle, to your electric drill.
Insert the paddle into the bucket and depress the drill's trigger to begin mixing the compound.
Continue to mix the contents of the bucket until the paddle spins smoothly and freely. Move the paddle toward the bottom and sides of the bucket to ensure thorough mixing.
Check that the mixture is smooth and free of lumps before applying it to your drywall or sheetrock.