09/03/2014 08:00 EDT | Updated 11/03/2014 05:59 EST

How to take your summer '90s trends into fall without looking clueless

TORONTO - Crop tops, slip dresses, overalls and fanny packs were just some of the '90s mainstays that have managed to creep beyond musical festivals and into mainstream fashion.

"We’ve seen the '90s come back in the last few years, but this summer I felt like I really saw it in full force," Flare's fashion director Tiyana Grulovic said by phone.

And the trend is being carried into fall, so don't pack away your strappy sundress just yet.

"I remember in 'Clueless,' (the character) Cher was wearing a strappy dress with a T-shirt underneath," said Grulovic, referencing the iconic film marking its 20th anniversary next year. “For a younger girl, a simple T-shirt under a spaghetti strap dress is beautiful.”

And for those who just can't let their crop tops go, Grulovic provides hope.

"If you have a crop top that you love, you can still wear it with something more high-waisted, like a high-waisted jean or trouser," said Grulovic. "I know this isn't for everyone, but I'm really into the '90s mom jeans."

Grulovic credits the French label Céline for bringing back minimalism, with its trademark muted colour palette and clean lines. "The concept of '90s minimalism, which is still going strong for fall, lends itself to more layering and wintry pieces," she said.

Head-to-toe knits were big on runways for fall 2014, with Céline, Marc Jacobs and Stella McCartney all doing versions of the look. While it doesn't translate well to the street, knits work well to propel summer pieces into fall.

"If you're looking for something a little bit more sophisticated, you might opt for pairing a turtleneck for fall with a really sleek column dress," said Sarah Smithers, fashion expert at Winners.

And if you're looking for an edgier look, adding tough-looking accessories to softer pieces will do the trick.

"Combat boots are a great complement to baby-doll dresses if you're trying to channel that grunge look," Smithers said. "Definitely '90s grunge is a great younger look that you can have a lot of fun with — with back to school that's a trend that always pops up in September."

Caitlan Moneta, fashion market editor at Fashion Magazine, credits Saint Laurent for the revival of grunge.

“There was a huge moment where he not only moved his head office to L.A. but changed the whole esthetic of the brand," said Moneta. "He went in a radical, younger, edgier direction — he was mixing plaid and fur and made high street look high end."

Grunge was the early 1990s musical reaction to 1980s hair metal, centred in Seattle and associated with bands like Nirvana and Pearl Jam. The look that became associated with the music was unassuming — flannel shirts and ripped jeans topped with unkempt hair. Twenty years on, it's been taken mainstream again by celebrities like pop singerMiley Cyrus and reality TV star Kylie Jenner.

"The good thing about grunge is that it's a lot about layering, so it's easy," said Moneta. "Like using a plaid shirt to your advantage — throw it over a slip dress or tie it around your waist and it's still in keeping with a grunge feeling, but it's adding extra layers and a little extra warmth."

To add polish, Moneta suggests completing your look with a biker jacket or adding heft to a slip dress with leather.

“Throw a pair of leather pants or leather leggings under something a little flimsier and it will add a little weight and a more modern, clean finish,” she said.

As for any '90s trends she isn't ready to take on, Moneta is cautious.

"I never say never. I work in fashion and it’s not in my vocabulary," said Moneta. "I said I would never wear crop tops — they're back; overalls — they're back. So never say never."