A sloppily cuffed jean. An ill-fitting blazer. A dress that shows just a little too much to be referred to as "tastefully sheer." These are the things that fashion editors and stylists can spot from a million miles away. To those in the biz, the proper proportions of a crop top may be obvious, but for those seeing the trends in a magazine or online, it can be a little trickier to know exactly how to wear everything.

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"How can I tell if my jeans fit properly?" "What's the most flattering shoe?" Both totally reasonable questions. With. Answers.

Ahead, you'll find advice from celebrity stylists who have been solving fashion conundrums for years. And we've taken notes from a few of our favorite iconic style stars—Jackie O, Bianca Jagger—and made some inferences ourselves. Here, 50 fashion tips that have withstood the test of time.