Full Instructions are here https://marinehowto.com/bed-it-tape/ but basically clean the area to be used, and put it on the surface. Bolt/screw down the hardware and trim of the excess that squeezes out. You may have to do the trim bit again a few weeks later. That's it - as bolted down, it squeezes out and seals around fastenings, although I tend to put some around the top of bolts and countersinks as well.