As far as sartorial matters go, the topic of undergarments tends to fall to the wayside. There are just too many other DDG duds vying for our attention, and let鈥檚 be real 鈥 if you had to choose between panties and a killer pair of trendy shoes or a flattering swimsuit, it鈥檚 pretty obvious which pieces would win out. That said, rockin鈥 the right (or wrong) underwear can really make or break an outfit. Seriously. Panty lines, rogue bra straps, ill-fitting underwear 鈥 they happen to the best of us, but can be avoided with this easy-to-follow advice. We鈥檙e giving you the low-down on eight common mistakes every girl makes in the lingerie department, plus a few solutions that will keep you looking your best, no matter what you鈥檙e wearing.

Not Trying It on Before Buying


1. Free People Daydreamer Underwire Bra ($48): Fit is essential when it comes to undergarments, and even the most swoon-worthy bra 鈥 this lovely lace number included 鈥 can lose its luster when the sizing is off. Bra shopping, in many ways, is very similar to shopping for a pair of jeans 鈥 every pair fits differently, especially across brands, so trying them on in-store is key. Your best bet is to get measured and fitted in person. Save the online shopping for once you鈥檙e more familiar with a brand鈥檚 sizing and styles.

Wearing Underwear That Doesn鈥檛 Fit Properly


2. Out from Under Everly Lace Cheeky Boyshort ($8): Just like an ill-fitting bra, pretty underwear that doesn鈥檛 fit properly is uncomfortable, as well as a fashion faux pas waiting to happen. Too tight or too loose, they run the risk of creating awkward bumps and lines under clothing, camel toe and a host of other less-than-desirable issues that are easily avoided. Weed out any underwear that falls under these two categories, and replace them with the proper size or seamless styles that stretch easily and won鈥檛 cut into your body.

Not Owning a Slip


3. La Perla Silk Slip ($194): We鈥檝e all done it 鈥 bought a slightly too-sheer dress that we never end up wearing because we don鈥檛 have the right undergarments for it. Oops. A neutral slip 鈥 white, nude or black 鈥 in silk or cotton fabric is a must-have for pieces like these, providing the extra coverage you need and preventing accidental wardrobe malfunctions (flashing your nipples to the world was definitely not on the agenda) from happening.

Not Following the Care Instructions Properly


4. Valentine NYC The Shangri-La Bra in Cranberry Red ($52): Always read the care instructions. Lace, silk and satin underwear and bras need a little extra love when it comes to washing, and shouldn鈥檛 be treated in the same way as their cotton counterparts. Delicate fabrics and constructions often require the use of cold water, hand-washing techniques, mild soap and air drying to maintain their like-new appearance.

Being Afraid of Shapewear


5. Jewel Toned Out All Night Mini ($38): Some pieces of clothing 鈥 we鈥檙e looking at you, bodycons 鈥 are a little more high maintenance than others in terms of what can be worn underneath. And that鈥檚 where shapewear comes in. It鈥檒l smooth out any bumps or lines created by bras or underwear to create a streamlined silhouette. This bright blue shaper would be the perfect piece to tuck under a form-fitting skirt or dress.

Not Thinking Outside the Strapless Bra Box


6. Hollywood Fashion Secrets Breast Lift Tape ($11): Strapless bras are one of those things every girl has in her wardrobe and absolutely hates to wear 鈥 they just always seem to fall short. But there鈥檚 hope 鈥 they aren鈥檛 the be-all-end-all when it comes to keeping the girls in check. Breast lift tape, breast shapers and stick-on bras are effective alternatives that make wearing daring duds a whole lot easier (and more appealing).

Not Wearing Seamless Underwear


7. Victoria鈥檚 Secret No-Show Sexy Cheeky Panty ($13): Hate the idea of lines? Ditch those classic cotton panties for seamless cheeky, boyshort or thong styles that send unsightly lines packing without the need to bust out the shapewear. Seamless underwear is also prime when it comes to working on your fitness. Ditch the thong when you head to the gym and pop a pair of these bad boys on under your leggings instead.

Not Getting Rid of Worn-Out Pieces


8. Victoria鈥檚 Secret Perfect Coverage Bra ($35): Yes, it can be hard to part with your favorite pieces of clothing, but there comes a time when you just have to let go. Bras and underwear that are wearing thin or sporting holes should be ditched and upgraded.

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