4 steps to skim coating 🕺🏼What is skim coating? The process of applying a thin layer of joint compound (think of it like a paste) to make your walls completely smooth! 1) Mixing When you buy the joint compound (commonly called mud) it’s a little too thick to use right away. It’s best if you add some water and mix it up till its cake batter consistency. You can do that by hand in a pan or in a 5 gallon bucket with a mixer attachment for your drill. 2) Apply�If you are working on a small area gr