Slipping big pots is easier than it seems. I slip all of my work at the leather hard stage. The pot is dry enough to pick up without altering its form. I keep all of my slips in a large 20 gallon tub. I place a board across it and put a shimpo banding wheel on the board. The pots is placed on a bat and placed on the banding wheel. I pour the slip over the pot. Any excess simply falls back into the bucket. When the pot is slipped, I clean the slip off the bat and move the slipped pot onto the table. Note: you can't see the banding wheel in these pictures, but it's there.