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1. Thou shalt not buy a tankini. They aren't as flattering as you may think. You get no real belly coverage, and the top hits at a bad spot. They're just as unforgiving as a bikini.

2. Thou shalt try a maillot. They're sexier than a string bikini! A one-piece with gathered fabric in the middle is as miraculous as a wrap dress: It instantly creates a waist and disguises bulges.

3. Thou shalt not wear prints if you're full-figured. You'll only look bigger.

4. Thou shalt pick a sophisticated color. Neons and graphic designs are better left to young women or surfer chicks.

5. Thou shalt not hide under a skirted suit. They age you. Cover up with a sarong or tunic.

6. Thou shalt choose a higher-cut leg. It will make thighs look leaner. Boy shorts are unkind even if you have toothpicks for legs.

7. Thou shalt not bother with a white swimsuit. It's good for glamour poses only.

8. Thou shalt buy a new bathing suit every other year. They lose elasticity and start to pill.

9. Thou shalt not even think about an unstructured top if you are larger than a B cup.

10. Thou shalt go shopping in the morning or at midday, before you're too tired.

See Adam's amazing swimsuit makeovers and find the perfect suit for your shape!

Plus, 7 swimsuit styles you should avoid, plus more tips for finding a perfect fit