In our era of all-casual everything, a hip blazer can perfectly split the difference between dressing up and cooling out. A great blazer should be sharp enough to wear to work, but also relaxed enough to do double duty for boozy weekend brunches and late-night dance parties. Like watches or hats, you want to own a few so you can cover all your bases.

The key, as always, is to invest in the best pieces you can afford and then style them up or down according to your social calendar and mood. A few key notes: A rounded or “patch” pocket will always read a bit more casual, while traditional “flap” pockets will be a little dressier. Most importantly, when trying your blazer on, make sure it sits cleanly on your shoulders. While any good tailor can lovingly tweak a blazer’s chest, sleeves or body, not even a master artisan can fix a bum shoulder. Aside from that, blaze up!

There are really only two rules when it comes to double breasted blazers. One is to let the simple elegance of the design (the snazzy peak lapels and extra buttons) lead the way—no need for bold patterns or crazy colors here. The second is to make sure you get one with some “drape,” or wiggle room, in the chest. A good double breasted blazer should float over your chest and midsection, creating a powerful, clean silhouette that proudly proclaims “power dresser” but whispers “great taste.”

One of the best investment pieces you can cop this fall is a twill blazer. We love this handsome version from Japanese brand Engineered Garments. Thanks to the casual nature of the fabric, a workwear-inspired cotton twill blazer will look just as rad with a bold flannel shirt and some Nike Air Force 1s as it will with a crisp Oxford shirt and some elevated loafers. With some smart styling, you could also wear it as an outer layer on a crisp day, giving you even more bang for your buck.

One of the easiest ways to look effortlessly cool is to dress tonally, which is just a fancy way of saying “wearing different shades of the same color.” For a perfect work/play look, make a dark blue denim/indigo blazer the star of the show and surround it with classic pieces like a light blue Oxford button-down shirt, a blue patterned tie and a pair of chic jeans. The best news? These days, a cool indigo blazer can be found for less than $100 at spots like Uniqlo or the Gap.

Indulge your inner mod with a super dapper checked blazer. Overcheck fabrics provide that perfect link between old-school elegance and rakish rebelliousness. They might look bold on their own, but when styled with a crisp white shirt and some dark blue jeans, overchecks magically transform into a basic. Back in the day, sartorial badasses like Keith Richards would pair their overcheck with some collegiate-inspired chinos and a pair of killer desert boots. We highly recommend you do the same.

If there’s one thing Italians have mastered when it comes to dressing, it’s the art of “dishevelled elegance.” This fall, invest in a lightly patterned unstructured blazer so you can style like a real sartorial maestro. The key to pulling off the look is surround your natty blazer with a few elevated basics—nothing too fancy. Not only do unstructured blazers pair perfectly with casual pieces like white sneakers and green chinos, they are meant to worn a bit rumpled, making them perfect for travel, either by plane or Vespa.