Years ago I discovered an old-fashioned device that not only helps me pack up the car, but also makes adjustments and suggestions if I’m doing it wrong.

The device is known as my father-in-law.

Somewhere in your family or Facebook you’ve got a similar device. If you don’t know who it is, think about who gives you turn-by-turn directions whenever you fire up your grill, or try to bowl.

If you’d rather not know who it is because you prefer packing the car by yourself, that’s fine. But just in case, consider these road-tested tips on having a better-packed and more comfortable car.

Do it the night before.

Unless you’re renting a car the day of your trip, give serious thought to packing up the car the night before, especially if “you hope to make an early morning getaway a reality,” says Susan Foster, author of “Smart Packing for Today’s Traveler,” who figures she’s packed and unpacked more than 5,000 times over the last three decades. If you get that early start and happen to have young children, Foster and travel writer Beth Blair suggest loading the sleeping tots directly into the car, perhaps bringing the pillows from their beds to ease the transition.

Load in and out properly.

You know the big suitcase your family shares for plane rides? Leave it in the closet. It won’t be easy to pack around, repack, carry, or access, especially for any emergency wardrobe changes. Sturdy soft-sided bags are not only easier to load and unload, but letting your older kids pack their own bags will teach them travel skills and curtail their complaints about what you brought, Foster says.

Have everyone bring their stuff to a central gathering place so you can do a mental inventory and “decide where things should go in the car based on when during the trip they’ll be needed,” Foster says. The basic strategy for loading car cargo is “last in, first out,” she says, “so the things needed at the hotel for the first night should be packed last.”

And if everyone packed his or her own bag, that doesn't mean you can't shuffle and consolidate their clothing, especially if you want to limit the number of bags you carry into the hotel, says Blair. “When traveling [between hotels], everyone can have their own suitcase,” she says, “but insist on family members sharing suitcases to be brought to the hotel room packed with one-night necessities — pajamas, change of clothes, toiletries. That way you're not hauling four or more suitcases in and out of the car every time and the room isn't crammed with luggage.”

Pack differently for one-stop trips.

If your road trip involves staying at just one place like a vacation home, alter your packing strategy, “devoting a quick hour or so to shopping for what you need to set up house once you’re settled” rather than trying to bring it all, says mother of three Mary Fiore, noting that over the years she “spent way too much time obsessing over what to bring, to the extreme discomfort of the entire family. We packed so much stuff that there was no room for comfort in the car. An hour into the trip, no one was happy and everyone was uncomfortable and cramped.”

Speaking of comfort.

If you allowed your sleepy passengers to bring their favorite pillows, get in on the act, perhaps with a personal travel pillow. “The one I carry is down-filled and it can overcome otherwise uncomfortable motel beds,” says RoadTripAmerica.com publisher Mark Sedenquist, who has spent 35 years and nearly a half-million miles on the road in North America. Another item he prefers not to hit the road without is his folding chair, which “can be set up and taken down with one hand in about 10 seconds,” he says, noting that there’s “nothing like being comfortable and away from the car for either a planned event, like a concert, or while waiting for fuel pump to arrive.”

Sedenquist also likes to pack what he calls a rescue bear. “It may sound corny” he says, “ but a teddy bear or other comfort animal can provide needed solace in an emergency, especially — but not only —to kids. The rest of the time, the bear can be your road trip mascot.”

Check your weight.

While you won’t encounter an airline staffer itching to slap “Heavy” stickers on your bags, you should still be mindful of your car’s payload capacity, or gross vehicle weight rating (GVWR), which is the maximum combined weight of all cargo and passengers that the car is designed to carry. The GVWR is usually indicated on a sticker on the driver’s door. Planning to stow luggage on top of your vehicle? AAA says to limit that load to a maximum of 18” high and no more than 100 pounds.

Always, always have full bars.

A fully-charged cell phone is a given on any trip, but also bring plenty of backup. Pack all available power sources for your phone – a spare battery, an alkaline or lithium battery-powered charger if one’s available for your phone, a USB cell phone charger that can be plugged into your laptop’s USB port, and, above all, a cell phone charger adaptable for your car’s lighter socket.

Consider keeping your cell plugged into the car socket during all your driving time, advises Blair, “since cell phones are likely to be constantly searching for a connection as road trippers drive in and out of service and the battery is using more power.”

For additional peace of mind, consider carting along a hand-held CB radio, Sedenquist says. Aside from enabling you to communicate with fellow radio owners in an emergency, many CBs permit you to tune in weather reports from the National Oceanic and Atmospheric Administration (NOAA), he says, best known for broadcasting advisories via its National Weather Service.

Pack these handy holders.

If you’re bringing an ice chest, Blair says to ensure it has “a working drain plug at the bottom to get rid of the melted water.” And almost nothing beats a laundry basket for versatility, she says, noting that it can be used for “beach toys and towels, transporting items between the car and hotel room, and of course, laundry.” She adds that the basket’s easy to pack, too. “Just place luggage inside the basket, or flip it upside down on top of the luggage.”

As receptacles go, there’s perhaps no item handier for traveling parents than disposable, gallon-sized zip-top bags, says mother of three Suzanne Rowan Kelleher, co-founder and editor-in-chief of family travel site WeJustGotBack.com. The bags “always come in handy for storing half-eaten fruit, almost-finished juice boxes, or anything else that's messy or wet,” she says, adding “I know this is gross, but they also make excellent barf bags if your kids are prone to car-sickness, since they keep contents, including smells, hermetically sealed until you can find a place to pull over and throw it away.”

No matter how you pack, what you pack, or how much, there’s one more thing that should always be in your car, says Foster: a folding luggage cart. It’s a gift that keeps on giving when you get home, too.

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