Stand the LP tanks upright, with the tank handle and dial facing upward. If transporting in a truck bed, put them in a cardboard box so they cannot tip over.
Wrap bungee cords around the box and run the hooks to side loops along the truck bed. You can use ratchet straps instead of bungee cords.
Push or shove the box several times to test the stability of your LP tank's upright transport.
Keep the LP tanks out of direct sunlight if at all possible. Shield the LP tanks with a blanket or cover.
Transport LP tanks in a cardboard box in the trunk if using a car. Do not transport them inside the vehicle.