Just dump a bottle in, fill up the tank, and drive long enough to get it in through the carb. I wouldn't put any more in unless you ran your tank way down and you re-filled it. Each bottle treats 20 gallons, so you could kind of adjust it if you topped off half a tank. I think my bag would probably keep out all but the most determined mouse. Here's a picture -- you drive in to it and then you zip it up just like you would a piece of pie. Last year, or maybe the year before, I made a point of taking photos of the brake rotors and some other surface-rust-prone parts and compared them both before, and after, the long winter's nap. They looked the same. The bag instructions say you can re-use the desiccant by heating it up in the oven, but I just buy new desiccant each year. It's easier to just buy new stuff.
