Open a bucket of joint compound and use a 6-inch putty knife to scoop out two clumps of joint compound and put them in a mud pan.
Fill the empty areas in the bucket of joint compound with lukewarm water.
Push a mud masher into the joint compound and repeatedly lift it up then push it into the joint compound to thoroughly mix it. Hit all areas of the bucket so the compound is mixed to the same consistency.
Remove the mud masher from the pail of joint compound and inspect the consistency of the compound. At this point it should resemble pancake batter. If the compound is too thick, add some more water and continue mixing it with the mud masher. If the compound is too watery, mix in some of the joint compound you took out of the bucket at the beginning.