This Video talks about how to store gas safely in your garage. This is NOT a video on how to store thousands of gallons but just enough (for a residential situation) to Bug Out or use your generator if you have to.
The more gas you store the better, but be safe! I forgot to mention in this video that you SHOULD NOT fill your gas cans up all the way so that the gas can expand in a plastic container. That’s why you should let the air out of the can every once in a while.
Have a number of fire extinguishers close by as a precaution (not just because of the gas). While gas can be stored for a long period of time under the right circumstances be sure to change it out every 6 to 12 months for best results.