As someone who is a diy but has drywalled 2 story homes, I can say this is the worst example of what to do. The mud you need to add a bit of moisture too so it doesn't crumbed and fall off the wall as you put it on. You shouldn't need to push it into the crack 5 times. When the tape was put on, you missed the crack! The tape helps prevent cracking in the future as expansion and contraction are real. It will crack in 6 months. In addition, you don't show the sanding, or what happens when it bubbles (if it does), how to do corners, or how to patch. Sanding had different methods, such as wet or dry.. and then how do u clean up the fine particles. No explanation. They are super fine and u can buy a compound to mix into the sanded particles to help sweet it up. If you vacuum it with a non HEPA vacuum, be prepared for the vacuum to suck it up and shoot the particles everywhere - don't do it. A small amount of dust, just use a damp paper towel. This is honestly the worst video I've ever seen. It's lacking skill, details, and I think any person learning should look at another video
