It's sweater weather – no doubt about it – and cardigans are the answer. The versatility factor alone makes them a wardrobe essential for every San Francisco man. And don't let anyone tell you a button-down knit isn't manly, because it is. In fact, men's cardigans are stylish, practical and quite flattering when worn correctly. Here's how. 

• When layering, it's particularly important to make sure everything fits to a T. By opting for a snugger fit, you can avoid any awkward looking (not to mention uncomfortable) bunchy under-layers. 
• The V-neckline on most cardigans is particularly flattering on men. Keep the whole look flattering by layering thinner fabrics underneath to avoid bulkiness.
• When dressing down, use thicker knits to add texture, and when dressing up, a slimmer, sleeker sweater can add instant sophistication. 

1. Theory Wilkson Button Cardigan, $235

2. Topshop Red Elbow Patch Vee Cardigan, $45

3. Folk Bobby Waffle-Knit Cardigan, $265

4. Levi's Cable Shawl Cardigan, $99.90

5. Monsieur Lacenaire Sheep Invader Merino Wool Cardigan, $430

6. Steven Alan New Shawl Cardigan, $189

7. Jack & Jones Intelligence Roco Cardigan, $107.43

Lily Ko (lily.7x7 @ gmail.com) studied fashion design and merchandising at Central Saint Martins and the Academy of Art University. In addition to writing for 7x7, Lily is an editor at SF Station, and works as a freelance stylist and apparel designer.