If it’s time to move on to bigger, better or just different digs, you have a decision to make: have the movers pack you (if you’re using movers) or pack yourself. Doing the latter can save you money, though it may involve a serious backache or two.

It can also lead to broken belongings if you’re not careful. And if you are using movers, you should know they’re not generally liable for the breakage of items you packed yourself (unless there’s obvious damage to the outside of the box), whether it’s your good china or favorite lamp.

Before you find yourself throwing things willy-nilly into boxes, take a few hints from the pros on avoiding mistakes people make when they pack themselves.

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Mistake 1: Waiting until the last minute. Start sorting and throwing away things you don’t need six weeks before moving day, says Michael Keaton, spokesperson for the American Moving and Storage Association (AMSA), a non-profit trade organization. AMSA recommends making three piles of stuff: keep, trash and donate. By donating what you no longer want or need, you’ll get a tax deduction. Or consider having a yard sale to generate a little extra cash.

“One month before your move, begin packing the nonessentials, like summer clothing if it’s winter,” Keaton says. Moving.org has a pre-move countdown checklist with suggestions on which tasks to do when.

Mistake 2: Using second-hand boxes. Buy new, high-quality boxes in a variety of shapes and sizes. Boxes that already survived one move are more likely to collapse from previous wear and tear, Keaton says. Professional movers and hardware stores have moving boxes for sale.

Besides boxes, you’ll need tissue paper, bubble wrap, plain newsprint, strong packing tape (not mailing tape) and marking pens. Want to be really organized about those boxes? “Smart Move Tape comes already color-coded and with the names of the different rooms on it, which makes identifying boxes much easier,” says Keaton.

Mistake 3: Making boxes too heavy. If you’re a bookworm and have a whole library to move, here’s a tip: Fill a small or medium box with books and make sure you can lift it. If you can’t, put books in a smaller box, and use more boxes. Otherwise, it’s a hernia waiting to happen. (Not to mention that a too-heavy box could break.) Keaton recommends cushioning the bottom of the box with bubble wrap or a similar material, layering heavy objects next and lighter items on top.

Mistake 4: Not filling boxes to the brim. Giving the contents of a box some elbow room is a bad idea. A half-filled box is more likely to collapse if another box is stacked on top of it. And the contents are more likely to shift around (and break) if they’re not snug. Jam any empty space with paper. If you can feel the items move around or hear them rattle when you shake the box, it’s not full enough.

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Mistake 5: Stacking dishes. You look at the stack of plates in your cabinet and assume that’s how you should stack them in the box. It’s not. The best way to pack dishware, says Keaton, is to line the bottom of a medium box with cushioning material (such as crumbled paper), then bubble wrap two of the same-size plates together. Arrange each two-pack of dishes on its side — in other words, the plates should be vertical, not horizontal. For glasses, stuff crumpled tissue paper inside before wrapping in bubble wrap. Label these boxes “fragile,” Keaton says.

Mistake 6: Moving empty suitcases. Place delicate or pricey clothing and accessories in your luggage instead, says Keaton.

Mistake 7: Packing folded clothes in boxes when a dresser will do. “If your dresser isn’t too heavy, the entire thing can be moved without taking everything out of the drawers,” says Keaton. For hanging items, get wardrobe boxes that let you take your clothes out of the closet and hang them on a bar in the box. These are pricey but they make populating your new closet a breeze.

Mistake 8: Transporting flammables. “Don’t take a chance on losing all your worldly possessions by moving flammable items,” Keaton says. Instead, give them away or take to a disposal site. According to moving.com, you shouldn’t move hairspray or other aerosols, nail polish remover, ammonia, bleach, cleaning solvents or lighter fluid, among other liquids.

Mistake 9: Storing used moving boxes indefinitely. “Companies called box brokers that specialize in buying and selling used boxes might be interested in giving you some money for your boxes,” says Keaton. “Or call a charity to see if they’d like them. And at the least, recycle them in your town’s recycling program.”

Ready to go? If you’re moving as a family, let the kids help. The Massachusetts Movers Association recommends giving them age-appropriate tasks when possible to prevent confusion about the move and help them feel like they’re part of the process. They can fill boxes with stuffed animals, toys or books, for example.

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