Just like Santa, you should always make a list and check it twice. Going into a grocery store without a plan is a good way to ensure that you'll forget crucial ingredients and buy things you don't need, which costs you money on the back end. And always check your fridge and pantry before you make your list so you don't double up on anything you already have. It's helpful to plan a menu for the week before starting your list. That way you can use the same ingredients in multiple dishes, which will save you the cost of having to throwaway unused perishables, such as meat and vegetables.