What’s the secret to perfect jeans? Time, effort, and the right amount of spandex.

Seriously.

Old Navy Flirt jeans, $29.50

Look for jeans with as LITTLE stretch as possible, like no more than 2%. It always seems like more stretch will be better, but it just means that the jeans wills stretch out more during the day. I really like the Flirt jeans because they are 80% cotton, 19% polyester, and 1% spandex; they look like conventional denim, but the polyester holds the color, and the VERY small touch of spandex keeps them from stretching out too much.

Try on multiple sizes (go up and down one size from what you think you wear) and err on the side of slightly snug rather than slightly loose. Jeans, no matter how much lycra or spandex they have in them, will stretch out; if you buy a pair that is baggy in the dressing room, they will be falling off by the end of the day. But don’t opt for a pair that you can’t button; those will never stretch enough.

Once you are sure about what size you need, try on more than one pair in that size for the best fit. Jeans, particularly at lower price points, are cut out on machines that can handle huge stacks of fabric all at once. The piece on the top of the pile can be an entirely different size than the piece at the bottom, even though they are both a size 12. I own two pair of Flirt jeans in the EXACT same size, but I probably tried on no fewer than three dozen pairs to find those two; the two pairs I bought were the ONLY ones that fit.

It would be great if we could ALL find jeans that fit perfectly off the rack, but that’s not always possible. Look for a pair that fits the most problematic part of your lower half and then work out from there. Wide hips? You can have the waist tailored. Big thighs? Again, the waist can be tailored. Don’t settle for jeans that are too tight in the hips and thighs, and don’t assume that you must wear jeans with a big gap at the waistband. Make the effort to have jeans that fit properly, even if that means a little tailoring. For most of us, the hip/thigh area is the issue, so stick with boot-cut jeans that fall straight from the widest part of your midsection. And of course a dark wash and longer hemline and slightly higher rise will make you look long and lean and proportional.

After going through all that to find jeans that fit right, you really want to take care of them. Wash jeans inside out in cold water, with the fly zipped and buttoned, and hang to dry. I am serious about the hanging; the dryer is the source of virtually all the wear your clothes see in their lifetime, and the heat will break down the stretch component of your jeans, which ruins the line. Jeans should NOT need to be shrunk to be wearable; if you are needing to put them in the hot dryer to make them small enough to wear, you need smaller jeans to start with. Keep chemicals and additives in the laundry to a minimum: no bleach ever, and as little detergent as possible. Again, you’re trying to preserve the fabric and lengthen the life of these jeans. Because otherwise you will have to start over and try on two hundred more pairs to find a replacement.

I find that my jeans have about a two-wearing life to them; after the second day, they are starting to sag and need to be laundered. Typically, though, I won’t even wear them a second day, because they’re usually baggy at the knees by then. If you’re trying to keep laundry loads to a minimum, you can either hand-wash your jeans (in cold water and gentle detergent) or just buy a couple more pairs and do one load each week. But don’t try to string one pair of jeans out for three or four days; you’ll just wind up wearing saggy baggy jeans.

I know that it seems oxymoronic to say that something as simple as jeans requires so much effort, but all of it — the shopping and the label reading and the laundering — is worth it. Having jeans that fit properly will change the whole way you get dressed; when your jeans fit, they make any outfit look that much better on you. I promise.

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