Drywall wet sanding does work, but it's not a panacea for all drywall woes. I think of it more as "drywall joint smudging" than actual sanding. But there is real value to smudging out the edges of the joints, because it makes the seams less visible or even invisible after painting.
- Large bucket.
- Drywall sanding sponge. Don't just use any sponge on hand. A drywall sponge is large, dense, and has abrasive material on one side.