I love good knitwear. Chunky, heavy-gauge sweaters, plush merinos, and various neckline styles, from crew to turtlenecks. This year has been unusually warm, but I’m thankful to be able to wear my sweaters again. A good knit can be a nice way to punch up a plainer, more casual outfit, as well as serve as an important layering piece under a tailored jacket. Some outfits don’t even look right without them – heavy parkas and bombers, for example, almost cry out for a sweater to be worn underneath.

Finding the right sweater entirely depends on your wardrobe, but I’ve found there are some general guidelines that can help almost anyone. These aren’t hard rules, per se, just suggestions on how to find something that will last, both in terms of construction and design.

1. Avoid Cheap Cashmere: You can find cashmere sweaters nowadays for as little as $75. And they’re all terrible. Cashmere comes from the soft underhairs of a goat, which means it takes an incredible amount of material and labor to knit a single sweater – from the gathering of the hairs to the spinning of yarns to the actual knitting. Cheap cashmere sweaters cut back in this process in two ways. The first is to use shorter fibers for the yarns; the second is to knit the sweater with more slack. As a customer, it’s almost impossible to identity these things when you’re in a store, but over time, you’ll find cheap cashmere sweaters pill and bag out easily. Unless a cashmere sweater is coming from a reputable company and retailing for over $400, it’s probably not worth your money. Instead, aim for other wools, such as Shetland, merino, and lambswool. They’ll offer you better value.

2. Be Careful with Cotton: A good, sturdy sweatshirt is incredibly useful, and some high-end cotton sweaters can also be nice. That said, many pure cotton sweaters, particularly on the low-end of the price spectrum, aren’t terribly great. Unlike wool, cotton fibers don’t have a natural crimp, which means they don’t spring back when stretched. Over time, without constant washing and drying – which will ruin your sweater anyway – a cotton sweater will start to lose its shape. I’m not as against cotton sweaters as I used to be, but when buying one, I think more about the reputation of the brand.

3. Think about Color and Texture: If you’re just starting to buy some nicer knitwear, stick with colors you can easily mix-and-match with other things in your wardrobe. Oftentimes, that’ll be navy, cream, and gray, which can be worn with tailored trousers or jeans. I also find textured knitwear to be more useful than the kind of smooth, plain-colored merinos you find everywhere. Those can be nice for layering under sport coats, but a cabled Aran or lofty lambswool sweater can be a great for adding visual interest in almost every other case. Aim for texture where you can.

4. Play Loose with Sizing: We’re sticklers for fit, but sweaters don’t have to fit perfectly. Knits are forgiving and can look perfectly fine – sometimes even better – when they’re a bit loose. If you’re concerned about it, know that some sweaters can be altered if you have the right tailor, or even DIY blocked at home to achieve what you need. You can’t make a size large fit like a medium, but you can make subtle adjustments. A lot depends on the sweater and what you’re trying to get, however, so read up on the possibilities before buying.

5. Softness Isn’t Everything: People often conflate softness with quality, but softness isn’t everything. Cashmere sweaters, for example, are sometimes put through a washing process to make the sweaters feel softer and more appealing to customers in stores. That same washing process, however, can break down the yarns and make them more likely to pill (not all cases, but often so). Similarly, some knitwear manufacturers will even spray their sweaters with a chemical to make them feel plush. A thick, plush sweater can be a wonderful thing, but don’t put too much stock in softness when shopping around. Trustworthy brands and stores are often more reliable indicators of quality.

For more on knitwear, see our guides on how to wash a sweater, how to take care of pilling, and general advice on knitwear care.