Remove old caulk with a caulk remover, utility knife, or scraper
Clean the joint thoroughly with soap scum remover or rubbing alcohol
Rinse and dry the area completely
Mask both sides of the seam with painter’s tape
Cut the caulk tube tip at a 45-degree angle
Pierce the inner seal of the tube
Load the tube into a caulk gun
Apply steady pressure and run a continuous bead along the seam
Smooth the bead with a caulk finishing tool or wet finger
Remove the painter’s tape before the caulk skins over
Wipe away excess caulk immediately
Let the caulk cure for the full time listed on the label
Avoid using the shower until the caulk is fully cured