Make sure your tires are properly inflated. Low-air tires will have more rolling resistance and reduce fuel economy. Some people will suggest inflating the tires too much, but I wouldn't recommend it, as it would cause uneven tire wear and increase the risk of damage, forcing the tire to be replaced if it hits a pothole or other road hazard. Don't put unnecessary trash in your car.
Unless you take your bike with you every day, keep the roof rack away until you go on a trip. If you have those sports team flags that some people put on their cars, take them out. You want to make your car more aerodynamic. Make sure your tires have the correct pressure.
Drive in such a way that you have to use the brakes as little as possible. Turn off the engine when not in motion. If you use heating or cooling, adjust it as close to the outside temperature as possible. There is an app called gas buddy that will allow you to see the prices in your area so you can choose the lowest one.
Try to combine errands in the same area so you're not crossing the entire city. Try to order the things you need, but not immediately online to have it delivered to you. The best way to save money is to have a vehicle with a higher mpg. Also make sure you keep up to date with oil changes and keep your filters clean.
All I did was step on the accelerator a little more gently. I had no problem keeping up with traffic. Underinflated tires can reduce fuel consumption by approximately 0.2% for every 1 psi drop in average pressure for all tires. I just downloaded the app backwards, they give you discounts on your gas at select stations of up to 25 cents per gallon.
I met a guy who removed all the seats in his Honda (except the driver's seat) to save money on gas. In fact, it's best to leave it running when navigating by inertia; modern fuel-injected engines generally cut off gas to the engine and rely on the car's momentum to turn it when it's running and decelerating. One thing you can do would be to get a credit card that offers good or at least decent money back rewards for spending on gas. The next step would be to see if there are any links between grocery stores and gas stations in your area.
Some service stations have a discount program, Shell, for example, has a silver level with 3 cents off per gallon or gold (6 reposts in 3 months, I think) with 5 cents off. I have a Costco membership for other reasons (our executive membership pays for itself), but I've heard that gas alone is worth getting a membership for many people. I fully believe that driving safer (not accelerating or shooting when I could) avoiding driving during times of heavy traffic and keeping my car in neutral most of the time at a stop, saved me a lot. Some service stations offer discounts for using cash instead of credit, you would need to see if one in your area does and if that discount exceeds the DU card cash rebate.
You can consider carpooling or using more public transportation, which could reduce gasoline consumption. I just bought a new car, and one of the things you end up doing with a new car is seeing how much you spend on gas. I have the Shell Fuel Rewards program, which saves me between 3 and 5 cents per gallon (the additional 2 cents depends on whether you can refuel a minimum amount every few months).
