Slideshow will continue in seconds. Click to skip
Patched-up denim is one of the main '90s and '00s trends I've been seeing on the runways lately. Click through for more fashion fad comebacks and easy ways to update each one.

The Trend: Flat sandals with socks

The Old Way: As anyone with a coveted spot on Delias' catalog mailing list 15 years ago knows, the only way to wear your Birkenstocks/Adidas slides/Tevas was with printed and rainbow-colored socks—bonus points if you had the kind with individual toes!!—and a good pair of bootcut jeans.

The Update: It's all about pairing irreverent footwear with something more fancy. You don't want your feet to be too distracting, though, so while you can keep the same '90s-inspired sandals, it's better to stick with solid black, white and grey socks this time around.

Click through to shop the look.

The Trend: Gaucho pants

The Old Way: Remember the stretchy jersey pants Jessica Simpson lived in around the time she filmed Newlyweds, aka the dorm room uniform of every girl attending college between 2001-2006?

The Update: To pull this off without looking like an extra in The Bling Ring, you've got to go for a pair made from more structured, non-clingy fabric. This helps in two major ways: 1. The style becomes much easier to dress up for situations that don't include hanging out by a pool. 2. It's about a million times more flattering on everyone.

Click through to shop the look.

The Trend: Slightly cropped leggings/tights

The Old Way: Paris Hilton's favorite Pinkberry run outfit, circa 2007: black leggings, denim skirt and Ugg boots.

The Update: Make both your shoes and skirt a little more ladylike—it offsets the casual feel of footless tights. No furry footwear, and no flip-flops!

Click through to shop the look.

The Trend: Embellished denim

The Old Way: Either patched up, sliding-down-your-hips (à la JNCOs) or aggressively flared bellbottom jeans with embroidered pockets. (Embroidered with what, you ask? With rhinestone butterflies, of course!)

The Update: Nothing too baggy or tight, and with surprising bursts of decoration—never any cutesy motifs or in-your-face logos. (Clever, hidden ones like Alexander Wang used in his Spring/Summer 2014 collection are okay, though!)

Click through to shop the look.

The Trend: Henley tops

The Old Way: Although henleys are technically never out of style, the tight, waffle-knit, baby animal-printed ones of 2008 are.

The Update: Get inspired by the grunge moment of the '90s and go for clean, super-simple styles with just enough slouch.

Click through to shop the look.

The Trend: Pointy-toe heels worn wide-leg pants

The Old Way: Just how Judy Greer's character in 13 Going On 30 would've styled it for a day at the Sparkle office: with skinny scarves and matching mini vests galore.

The Update: First of all, never, ever, ever pair it with a mini vest or any shirt that falls into that early-aughts "going-out top" category. A less-is-more approach works best for this outfit, so go with a basic pullover or button-up instead.

Click through to shop the look.

The Trend: Lace-front pants

The Old Way: Second-skin bellbottoms all the way, baby. I had a corduroy pair by Paris Blues that were neither from Paris nor blue, but still the best thing ever!

The Update: It's okay to still go with something fitted, but it shouldn't have a hugely-belled hem; slightly cropped or slightly flared is the way to go. Then, to avoid any Coyote Ugly moments, be sure to pair it with something a little looser up top.

Click through to shop the look.