Slip Trailing

Step 1 — Fill a slip trailer (a small squeeze bottle with a fine tip) with slip about the thickness of heavy cream.
Step 2 — Practice on a scrap of clay or newspaper first.
Step 3 — On a leather-hard pot, squeeze gently and steadily: dots, swirls, vines, lace.
Step 4 — Keep your hand moving. A pause leaves a puddle.

It's like decorating a wedding cake, only this one lasts forever.