Jolie Hettena and Marli Hettena, 17, of Merrick, wear comfortable...

Jolie Hettena and Marli Hettena, 17, of Merrick, wear comfortable outfits and backpacks for their flight at MacArthur in Ronkonkoma on April 19. Credit: Morgan Campbell

In May, Michael Doyle and his wife head out from their Levittown home for a getaway to Copenhagen, where galleries, gardens, museums and more must-see sites will all be at their feet. Weeks before he departs for Denmark, Doyle, a flight attendant for a major carrier for 35 years, already knows what he’ll have on his feet during the flight: a pair of his trusty slip-ons. They come in handy passing through security and in the cabin.

“I like to wear loafers. You can slide them on and off at your seat,” he says, adding an inside tip of the trade. “Always wear shoes when you walk anywhere in the plane.” More than comfy, slip-ons come in a variety of styles for men and women — Cole Haan to Toms to Tom Ford.

Brayden, 5, Kaitlin, and Gemma Kenney, 6, from East Islip,...

Brayden, 5, Kaitlin, and Gemma Kenney, 6, from East Islip, travel in Disney-themed attire at MacArthur in Ronkonkoma on April 19. Credit: Morgan Campbell

With more than three decades of work experience in the sky, plus his frequent personal journeys, Doyle has solved the puzzle of what to wear when you’re at 35,000 feet.

To help make sure your next flight is nothing but blue skies when it comes to comfort, style and safety, we've rounded up advice for in-flight apparel from pros in the flying industry and parents who log frequent air miles.

Flight attendant tips

Stretch your style

Stretch jeans are a flyer’s best friend, if you ask Chris Riebli, a flight attendant for one of the “Big 3” U.S. airlines for more than three decades who lives in Long Beach. That goes double on a long-haul flight, where tight, binding clothes — as in, skinny jeans — are as unwelcome as turbulence.

“I always wear jeans because jeans are a little bit heavier and bulkier to pack so it takes packing space,” she says. “You can pretty much wear your jeans anywhere in the world and then fit into what everybody is wearing there.” Just make sure they're of the stretch variety, “so they're more comfortable,” she says, adding that jeans have “come a long way” from the old days of being stiff and unforgiving. On a nine-hour flight, that’s a top priority. You can find these wardrobe staples wherever you like to shop, from Nordstrom to Macy’s to Marshalls and beyond.

Layer it on

Like her fellow flight attendants, Leiann Cummings, who works for Breeze Airways and lives in Center Moriches, is a true believer in dressing strategically when she’s in the air. “My big thing is layers,” she says. “You want to layer up because being in the cabin is always unpredictable.”

Riebli echoes that sentiment, noting that the climate can turn from arctic to tropical as you go from tarmac to cabin. “You never know what the temperature is going to be,” she says. So she always pairs a top — short- or long-sleeve — with a “nice fashion sweatshirt, sweater or lightweight jacket.”

Focus on fabrics that breathe

Reign Small, 3, and Ryan Small, of Brooklyn, travel in casual...

Reign Small, 3, and Ryan Small, of Brooklyn, travel in casual and breathable attire at MacArthur in Ronkonkoma on April 19. Credit: Morgan Campbell

Choices for fashionable, travel-friendly tops are as vast as the open sky. Since you can boost in-flight comfort by wearing breathable fabrics, such as cotton, Uniqlo in Valley Stream, Uniondale and Huntington Station and the Gap (multiple locations) are two shops for in-flight inspiration. Moisture-wicking and quick-drying human-made fabrics found in athleisure wear are another option. Alo in Roosevelt Field and Lululemon in Uniondale, Manhasset and Huntington Station are two sources for going this style route.

Jill Hettena, of Merrick, wears comfortable shoes to travel.

Jill Hettena, of Merrick, wears comfortable shoes to travel. Credit: Morgan Campbell

Choose the right shoes

Flight attendants agreed that open-toed shoes are a no-no for flying, so stash your stilettos, strappy sandals and playful flip-flops in your bag. “I always recommend close-toed shoes,” says Cummings. “It’s a lot safer and your feet don’t get cold.”

Riebli is an ace at packing with maximum efficiency. She always matches her in-flight footwear to the environment of her destination. For a trip to Iceland, where hiking was on the agenda, she wore her comfy Nike running shoes. En route to Paris and England, she wears her suede tennis shoes. “They’re a little more fashionable and good for walking.”

Travel agent advice

Penny Cuomo has been running Sunset Travel in Bellmore since 1988. She’s logged countless miles planning trips for others (upcoming is one to the Canadian Rockies) and herself.

Cuomo figures she flies at least four times a year, and she dresses for the trip in essentially the same outfit. “I wear leggings or cropped pants, a T-shirt and a sweater or zipper top layer,” she says. “And comfortable shoes. Sometimes you have to walk a mile to get to the baggage.”

Wrap it up

“I tell the women to take a shawl and men to take a sweatshirt,” says Cuomo. “It can definitely get cold in the cabin.” During a long flight, a wrap or pashmina easily doubles as a makeshift pillow and takes up practically no space in a carry-on bag.

Have it in the bag

Crossbody bags are designed to keep your essential documents including passports close at hand and safe. “I tell everybody to wear one,” says Cuomo. “Everything is at your fingertips — and no one else’s.”

There are many styles — Cuomo’s favorite is MZ Wallace in Manhattan — and most feature adjustable straps for just the right fit. Riebli seconds the crossbody bag tip — her go-to brand is Dakine, found at sporting good locations like REI in Huntington Station and Public Lands in Melville.

Mom memo

Sloane Grober, 34, a mother of three and retail consultant who lives in Syosset, reckons that she flies about eight times a year between family trips, jaunts with just her husband and the occasional girls’ getaway.

Flying with her three daughters — Hunter, 9, Harlow, 6, Hayden, 3 — brings out Grober’s strategic team captain. “I tend to dress all my kids in coordinating outfits,” she says. “It’s easy for everyone around us to know that we're kind of a pack or a pod.”

Sisters Harlow, 6, Hayden, 3, and Hunter Grober, 9, wear...

Sisters Harlow, 6, Hayden, 3, and Hunter Grober, 9, wear matching outfits when they travel. Credit: Howard Simmons

Have hoodie, will travel

“My number one rule for flying is that everybody wears a hoodie,” says Grober. “When my kids are sleeping on the airplane in their hoodies, I’m not so concerned about where their head is resting.” Her go-to shops include Blue Jean Baby in Woodbury and Gold Coast Kids in Jericho.

Prioritize pockets

When you’re flying, you can never have too many pockets, according to Grober. Leggings with a deep cargo-style pocket are a must-have in her plane outfit. “I always wear the same pair of black Lululemon leggings,” she says, adding that it’s ideal for boarding passes. “I love that they keep my hands free and nothing can fall out.”