A caulk gun is a pretty common household item. However, if you ever find yourself searching in vain for a caulk gun then there's a simple solution that can save you a trip to the hardware store. All it requires is a wood clamp, a small stick of wood, and zip ties. Fasten the caulk to the wood clamp using zip ties and place a piece of wood in the back of the tube and you have an improvised caulk gun.
Actually, there's really no need for a caulk gun ever again if you happen to have these items lying around the garage or shed. It works pretty much exactly like an actual caulk gun.