Clear Silicone Sealant

1 Insert the clear silicone sealant into the caulking gun. The caulking gun is a round, metal cylinder that will receive a tube of silicone sealant. It has a metal rod inside that pushes through the rear of the tube of silicone sealant and forces the butyl sealant out of a tip on the end of the silicone tube. By pressing a handle on the end of the caulking gun, you can control the amount of silicone that is dispensed.
2 Trim a small piece (about 2 inches long) off of the plastic tip located at the end of the sealant tube. The tube is about 1/8 inch wide at the very tip, and it flares out to 1/2 inch at the point where it attaches to the cylinder of sealant. Start with a small piece and then work your way up to the desired hole size as you need to.
3 Poke a long nail up through end of the tip and pierce the foil seal located inside the tip and at the base of the polysulfide sealant tube.
4 Press the tip against the area to be sealed and gently squeeze the handle located at the top of the caulking gun. Once you are done with the application, release the pressure from the caulking gun by disengaging the metal rod at the handle. Failure to do so will result in sealant leakage.
5 Smooth the bead of silicone sealant out with your finger. Clean up any excess silicone with a rag and paint thinner.