#7. Make a list
Always make a list, especially if you’re going to the store to buy some stuff. Without a list, you will always leave getting more stuff than you actually needed. So if you went to a store to get eggs and milk and you get out with a lot of more stuff than you intended too, then you need to take your list of groceries next time. That means you will only get the stuff you need, and if you end up getting other stuff that is not on the list, then abort the mission and don’t leave the store!