How do you guys set up your gallon jugs of fuel without letting air get to the fuel? I have a manual fuel pump and I was thinking I could just put one line on it with a clunk, and another line to connect to the model's tank. Then just put the original cap on the jug when I'm not fueling. I know this sounds like basic knowledge, but I haven't been active in the hobby for a few years and can't really remember how people used to do it. Thanks.

-Patrick