The night before you leave:

First, shut off the water main in your basement. Then, using a hacksaw,
cut a notch out of the main supply line. Follow the same procedures
with your gas line.

On the morning of departure, turn the water and gas back on, and head
off to vacation.

This method is the easiest of all sugegsted ... and it has the added
benefit that you won't have to wonder if anything has gone wrong back
at home while you were away.

(smiley face)