The construction madness at LaGuardia Airport has left fliers facing misery like never before.

The Post spoke with experts, frequent fliers and LaGuardia workers to map out the ultimate survival guide to one of the nation’s worst airports so travelers can get in and out with fewer headaches.

When to fly

The best way to beat the crush to the terminals is to plan your flights around the mayhem.

The busiest times at the airport are from 6 a.m. to 9 a.m. and from 4 p.m. to 8 p.m. And the busiest days are Monday, Thursday and Friday. So aim for midday and midweek. Luckily, those slower days are also when flights tend to be cheaper, according to Eric Hrubant, owner of CIRE Travel in Manhattan.

Cabbing it

Most travelers in and out of LaGuardia take cabs. But sometimes, the directions on a driver’s GPS are not the best or will lead straight into stop-and-go traffic.

Check traffic apps like Waze before you leave the house and be prepared to direct your driver based on that data. It sometimes makes more sense to get dropped off in the residential neighborhoods across the Grand Central Parkway. Pedestrians can cross on the 94th Street Overpass.

When flying in, open your ride app the second the plane touches the ground for instructions on leaving the airport.

“As soon as the plane lands, check Uber to see how long it’s going to take the driver to meet you there; if you see it’s going to be 10 minutes, schedule it as you’re getting off the plane,” said Michael Bieszczad, 44, vice president of an investment management company. “You have to time it, because they can’t stand outside and wait for you.”

Public transit

Last year, the MTA made the Q70 bus between the 7 train and the airport a Select Bus Service and rebranded it as the LaGuardia Link. The bus goes directly from the subway to the airport, making it the easiest way to get there without a car, but of course, it will get stuck just like other vehicles when traffic is rough. LaGuardia Gateway Partners has promised an AirTrain and ferry stop, but those are years off.

Driving in

The easiest lot to get to and park in is Terminal D. That terminal houses Delta and WestJet, so fly those if you can. The less time you can spend in your car, the lower your stress levels will be.

Terminal C, the LaGuardia home of US Airways and where there are also more Delta flights, is farther away and the parking lots fill up faster. It’s not hard to get to when traffic is mild, but when cars are crawling, it can take 15 minutes to half an hour longer than pulling into Terminal D.

Most of the airlines operate out of Terminal B, and parking is a long way out of the way. On high-traffic days, getting here can be a nightmare, according to passengers.

“You think you’re early, but you’re not early enough,” said Lou, who was trying to find parking in a double-breasted business suit. “I started out in Terminal B, now I’m in D, and I have to go to C because I’m been turned around three times.”

In-the-know fliers also suggest booking parking ahead of time to avoid fussing with it at the gate.

As with cabbing, if you’re driving, you don’t have to even bring your car to LaGuardia at all. Many people park in residential neighborhoods nearby and cross Grand Central Parkway to the airport.

Frequent flier EK said he has developed an encyclopedic knowledge of the side streets just across the Grand Central Parkway.

“Go on the local road or go crazy,” EK said.

If parking on a residential street, make sure to take note of the alternate-side parking rules. If you time your flight right, you can potentially park for a full week for free.

Some people don’t even worry about getting a ticket, since the $35 fine is still cheaper than long-term parking at the airport. But cops do have the authority to tow a scofflaw’s car, so beware.

Or take a bike. Some travelers strap their baggage on their backs and bike to their flights. There are bike lanes on some roads leading the airport, and LaGuardia now has racks for fliers and employees.

Treat yourself

There aren’t yet any massage therapists or even massage chairs at LaGuardia, but there is plenty of food and drink therapy available if you know where to look.

Grab a taco at Vuelo Taqueria, oysters at The Minnow or some fine wine at Wibar.

Delta has a program called Desire that lets fliers order food and drinks and have them delivered to them from their seat at the gate.

If you’re flying out of Terminal B, bring food with you — but not soups or other liquids that will get snatched away at security.

“That’s one bad thing about this terminal: There’s no restaurants inside,” said Bieszczad. “So you’ve got to eat before you go in there.”

Getting around

Once you make it into the airport, workers at LaGuardia are less than helpful, according to frequent fliers, so you’ve got to find your own way around.

“Don’t ask for help from the attendants, because often you’ll be directed to the wrong area,” said Mark Lande, 27, a marketing developer from Bushwick. “There’s a high chance that they either don’t know or point you in the wrong direction. You have better luck figuring out for yourself.”