Tip 1: Sand it well and watch out for the dust. When you're sanding compound, the dust will go everywhere. Make sure you seal off any vents and turn off the air conditioning so it doesn't draw into the systems. When you're ready to sand, there's a good chance that there will be dust. If it's just one room in a house, put a plastic drop cloth at the doorway. If you don't want any dust, you can use sponges. With the sponges you'll have to let it dry, though.
