Enter: the oversized denim jacket. "Styling something oversized ... from big and boxy to a vintage trucker style or more of a boyfriend look," says Alissa Friedman, senior public relations and ...

These days, denim jackets are featured in a slew of cuts and silhouette’s from boxy fitting to waist cinching. The AE Ex-Boyfriend Denim Jacket is the most classic approach to a jean jacket.

If you click on links we provide, we may receive compensation. Taylor Swift, Mandy Moore, and more stars wear denim jackets, too Alyssa Grabinski is a senior shopping writer for PEOPLE.

Oil Green’s look was also very Sienna Miller, largely thanks to his khaki-toned Frame denim jacket, which he layered over a black hoodie. But what makes this look so Sienna Miller coded?