Step 1: Wipe off the wall surface with a damb sponge and let it dry (you don't want dust in your caulk).
Step 2: Place your tube of caulk in the caulking gun, with the pointed end facing out (kind of obvious, but you know, just being thorough here). Turn the "key" at the end of the caulking gun (near the handle) so that the tube is firmly in place.
Step 3: Cut the tip of the tube at an angle. If you're filling in a small crack, cut toward the very end so there's just a small hole. If you're filling in a larger space, cut lower for a larger opening.
Step 4: Hold the caulking gun against the wall, placing the tip of the tube flat against the far end of the crack (or the top, if it's verticle). Push down on the gun's handle with steady pressure and move along the crack without stopping. Warning: If you do
stop, the caulk will continue to come out of the tube, leaving you with a big mess.
Step 5: Run your finger along the caulk line to smooth out any clumps, or, for a super smooth finish, use a business card.
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