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Road trips are easier to pack for than trips on an airplane because of the simple fact that you have more room for bags.  Here's some quick tips for packing for a road trip:

• Separate - When packing your bags, separate your clothes from others to keep unpacking easy and effortless.
• Consolidate - Try to fit the big stuff into their own bags; for example, put all your sweatshirts, sweaters and jackets into one large bag (I recommend a trash bag for flexibility, and you can throw it away after unpacking)
• Divide - Take apart chargers and other electronic accessories to easily store them into a backpack or other easy carrying bags that are closable.  You don't want to keep your expensive electronics in the same bags as your clothes and larger equipment, nor do you want them misplaced around the car.

Packing the car:

• The easiest way to go about packing your suitcases into the car is to start with the largest luggage in the trunk and piling on top of that.
• Although this may take some skill and patience, make sure to keep the windows clear of obstruction as much as possible.  So, if you're piling the bags up too high, try to rethink your packing strategy.
• Keep the smaller bags such as backpacks, purses and daypacks in the backseat instead of the trunk.  Considering that you're going to pack more valuable and breakable objects in the smaller bags, keep them far away from the large bags.
• Take advantage of extra storage areas around your car.  Lots of new model SUVs and Sedans come with extra storage space in the trunk and under the seats.
• Food and water!  You're going to get hungry and thirsty during your journey, so save stop-time for bathroom breaks and gas by packing food and water to tide you over.
  • I suggest snacks such as granola bars, apples, bananas, oranges (the peels make a mess though), trail mix, and maybe even celery with peanut butter (if you're able to keep a clean backseat).
  • For drinks, I suggest water bottles (Nalgenes and SIGGs are better because they hold more than a regular plastic bottle), sport drinks (Gatorade, Powerade, Vitamin Water, etc) and maybe a little soda to keep your eyes open.