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Use a tape measure to take the dimensions of your luggage. It's easy to estimate the size incorrectly and end up with packing cubes that are wider than your suitcase. To avoid this, always make sure to check the packing cubes' dimensions and compare with your luggage before purchasing. Small cubes are perfect for keeping a bunch of loose items together, such as toiletries, swimsuits, belts, hair accessories, or electronics. These items can easily get lost when left loose in a suitcase or bag, but packing cubes keep them organized in one place and easily accessible while you travel. This size is perfect for holding thin, flexible clothes that can be easily rolled up. For example, you could fill a medium cube with T-shirts, shorts, workout clothes, underwear, and socks. It also works well for small day trips that require a quick change of clothing. Fold or roll your pants, jeans, and sweatshirts, and stack them inside larger cubes. This size also lets you fit clothing in easily and prevents wrinkles, rather than requiring you to squeeze or bunch up the fabric to get clothes to fit. These cubes let you keep your dirty laundry separate from your clean clothes, reducing mess and odor within your luggage. Some double-sided cubes even have a water-resistant half for wet swimsuits and towels, making them perfect for beach trips. If you're not sure what size or how many you'll need, start with a few smaller packing cubes. This way, they'll fit in any suitcase and allow you to test out the organizing process. Plus, having less cubes will help you avoid overpacking. This also gives you more versatility when switching luggage. Larger packing cubes may be difficult to match with different sizes of luggage.
Measure your luggage before you purchase a packing cube. Use smaller cubes for toiletries and accessories. Pack medium-sized cubes with light clothing. Fill up larger cubes with bulkier clothing. Use double-sided cubes for laundry storage. Start by purchasing small cubes.