Will you be hitting the roads this holiday season? Tweaking your driving habits can save you loads of money on gas. Of course, nothing can beat ridesharing when it comes to conserving energy. Combine the following tips from NatGeo with another passenger and you'll save your wallet and the environment. Have a wonderful holiday, and we'll see you in 2012!

Step 1: Drive more calmly. Aggressive driving, which includes excessive acceleration and frequent braking, wastes gas. Go with the flow of traffic, and don't try to always pass other cars. Not only is this safer, but it can improve your mileage by up to 33 percent on the highway or 5 percent in town. (See References 1)

Step 2: Follow the speed limit. Most cars reach their optimal efficiency between 45 and 60 miles per hour. Efficiency decreases rapidly above 60 mph. You'll save money, too: If gas costs $3.52 per gallon, for example, each 5 mph above 60 mph costs you an additional 24 cents per gallon. (See References 1)

Step 3: Pack only what you need. Every additional 100 pounds of cargo in your car reduces fuel efficiency by 1 to 2 percent. Smaller cars are more heavily affected than larger cars. (See References 1)

Step 4: Don't use roof racks unless absolutely necessary. Whenever possible, put gear in the trunk rather than on the roof rack, where it causes aerodynamic drag and reduces your gas mileage. (See References 2)

Step 5: Turn off the air conditioning. Use your automobile's flow-through ventilation system or open the windows at lower speeds. Running the air conditioner can reduce your mileage by up to 20 percent. (See References 2)

Step 6: Don't idle, especially if you'll be waiting in one spot for more than a minute. Idling for 10 seconds uses about as much fuel as it takes to restart the vehicle, so it's more efficient to turn off the engine while you wait. (See References 2)

Step 7: Use cruise control and overdrive gears, especially for long highway trips. (See References 1)

Step 8: Check your tire pressure once a month. Inflate your tires to the pressure listed inside the driver's side door or in the owner's manual. Do not inflate to the maximum pressure printed on the tire itself. Properly inflated tires last longer, are safer and can improve gas mileage by about 3 percent. (See References 3)

Step 9: Plan your outings to avoid rush hour. Driving during busy hours means more braking, more idling and more wasted gas. (See References 2)