Prepare the surface: Remove all old caulk, dirt, grease, and residue. The surface should be clean and completely dry. DAP recommends rubbing alcohol for removing soap film. Prepare the tube: Remove the cap and cut the nozzle at a 45° angle to the desired bead size. If using a cartridge, load it into a caulk gun. Apply: Fill the joint with a continuous, even bead of caulk. The joint should not exceed 3/8" wide × 3/8" deep. Smooth: Tool or smooth the bead before it skins over. Clean up: Wipe excess wet caulk with a damp sponge. Clean hands and tools with warm water and soap. Curing: Allow at least 2 hours before painting and 36 hours before exposing the caulk to water. Longer drying times may be needed in cool or humid conditions.