These are by far the easiest pieces to mix. The cut fits all body types and the style can be added to everyone's closets. Plus, grey and plaid work as neutrals so having some fun mixing patterns is welcome. Above (from left) jersey wide leg pant, $20, is available at Nasty Gal. Acne Studios checked wide-leg cotton-blend trousers, $189 available at Barneys New York. MSGM wool straight-leg plaid trousers, $143 available at Bergdorf Goodman.