Don’t let the gas tank get below a quarter tank.
In the event of a rushed morning before work, or worse yet, a real emergency, you won't have to make another stop; and you'll never wind up sitting on the side of the highway during rush hour awaiting the tow truck with a can of gas.
Keep a well-stocked pantry.
Always have enough non-perishable food items and bottled water on hand to feed your family for 72 hours. Stock up on items you know you'll actually eat, including basics like tuna, peanut butter, jam, canned fruit and veg, canned spaghetti, a frozen loaf of bread, granola bars, etc. If the budget gets tight, the car breaks down, or a local disaster occurs, you'll be okay for those first three days.
Maintain a supply of home staples.
When you open or unwrap the last of any item that you regularly use -- detergent, shampoo, conditioner, bath soap, dish soap, toilet paper, paper towels, dog food,Tylenol -- put that item on the grocery list and purchase it on your very next trip. DO NOT WAIT until a basic is nearly gone. If you have the storage space, buy several when these items are on sale to stretch the budget.
Buy bus passes, metro cards, postage stamps, etc. before the current items expire or run out.
When you only have a few uses left, write a note in your calendar as a reminder and make the purchase at the next opportunity. You'll avoid missed meetings and late fees by delivering yourself and your mail on time.
Mark gift-giving events on your calendar, including a shopping trip the week before.
You'll budget better and purchase more thoughtfully when you shop early, not as you drive to the wedding, shower, birthday party.