Just take off the hose,, I use a plastic cap to go over the thread part of the faucet. Take the plastic . rubber ring and place around the faucet bottom , place the cover around fully and pull the outside of the rubber string . It has a little push tab you hold in while pulling. The cover tightens with the foam against the siding and lock. If the siding has a bot of open underneath , just put in some foam or sponge to close up
The item is very fragile, and I imagine it is not worth it to Home Depot to package it. You can buy similar stuff off Amazon - but you aren't going to pay $1.18 for them!