En español | The tendency when packing for a trip is to throw in everything — just in case. A chance of rain, and you're stuffing in rubber boots; the possibility of down time, and you're packing your entire library. The first step toward streamlining is to eliminate the items you truly don't need. These guidelines on what NOT to pack will keep your luggage bulk in check.

Use these tips to avoid over packing and streamline your luggage bulk. — Photo by Mark Weiss/Getty Images

1. Items Prohibited by the TSA
If you're flying, check with the Transportation Security Administration to see whether anything you plan to pack is prohibited. The TSA website has clear guidance about what's allowed and what's not: in carry-ons, checked luggage or both. When in doubt about an item, leave it at home.

2. Regular-Sized Toiletries
Full-sized bottles of shampoo and lotion are heavy, take up precious space and, because of TSA 3-1-1 guidelines, make carry-on flying impossible. Create a toiletries kit with trial-sized drugstore sundries (toothpaste, deodorant and the like) and plastic bottles or jars filled with favorite products. A trip is also a great opportunity to finish off those almost-empty tubes of toothpaste and cosmetic samples. If you frequently visit a friend or relative, ask to keep a stash of your favorite products at his or her house.

3. Nonessential Clothing
Every article you pack should pull double-duty so build a mix-and-match, neutral-palette wardrobe. Use easy-to-pack accessories — scarves, shawls, ties and belts — to add a pop of color and transform daytime outfits into evening ensembles. Active-wear items work well for sports/outdoor activities and sightseeing. Hand-washing allows for fewer items. Opt for quick-drying, wrinkle-resistant fabrics; avoid those that require ironing or dry-cleaning. Also select the lightest fabrics possible. For cold climates, this means hand-washable silk and ultra-light fleece instead of bulky wool or cotton. It also means a coat you can wear in transit; the best are light (down coats are great, as are trench coats with removable linings) and just large enough to accommodate layers.

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