I'm a former international flight attendant. Here are 11 ways to improve your experience on long-haul flights.

After logging countless airline miles as a plane passenger and a former crew member, I can attest that domestic and international flights are entirely different animals.

If you're a seasoned domestic traveler, use these tips to optimize your international flying experience from the time you book your trip to the time you arrive home.

Most international airlines allow passengers to check two bags for free.

But before you stuff your entire wardrobe into vacuum storage bags, which are a godsend for saving space but a truckload of extra pounds, know that airlines, especially foreign ones, usually enforce weight limits.

Some of these airlines have stricter luggage policies than domestic airlines and often have a weight limit on carry-on bags as well.

Most international flights start boarding a full hour before departure and close the doors 15 minutes prior to take-off. So, make sure you plan your arrival time accordingly.

Don't show up too early, though.

Many international airlines and US airlines at international airports won't allow you to check in or drop off bags until an allotted time before your departure, so responsible early birds may have to stand around outside security if they show up too early.

If you're used to the glorious feeling of using TSA PreCheck to saunter through security, be aware that airport security in many countries outside of the US requires you to remove liquids, outerwear, and in some cases, shoes when you fly internationally — even if you have TSA PreCheck.

Don't get caught off-guard, or else you may end up rifling through your carry-on for a ramshackle collection of toiletries and sweating under the harsh lights as a line piles up behind you.

Wear socks that your harshest critic would sign off on and pack your liquids in quart-sized, transparent, and resealable plastic bags. Or consider going liquid-free, which is easier than ever with solid shampoo, conditioner, and lotion bars.

Just because an airline will sell you a ticket with an hour or 90-minute connection doesn't mean you're guaranteed to make said connection.

Between flights, you may have to collect your checked bags and navigate some kind of checkpoint.

For example, when arriving in the US, travelers usually have to clear immigration and customs; take a long walk, tram, or bus to a different terminal; and then start the entire security process all over again with the newly arrived crowds.

In most cases, airlines consider it your responsibility to arrive at the flight's gate on time, even if they advertised a pairing with a tight turnaround time or changed your itinerary to that pairing after you booked.

Searching high and low for the cheapest airfare can feel like a sport.

However, the money you save when you buy your ticket may feel like chump change when you're separated from your companions or squished in the middle seat of the last economy row for over 10 hours.

That said, check online reviews before springing for that bulkhead, exit row, premium economy, or even business-class seat.

Aircraft specs and airline offerings vary, so you should ensure that the plane will have space and service that make the upgrade worth the extra money.

Window shades must remain open for take-off and landing so the crew can see outside during an emergency, but you should close them after that.

No matter how dark it is when you depart, the sun will probably start rising long before you and the rest of the cabin are ready to wake up.

If you don't want flight attendants to wake you every time the seatbelt sign blinks on, buckle up over your blanket so the crew can clearly see you're strapped in.

Waking passengers up may seem like overkill, but realize that your life can depend on that belt if severe turbulence hits. The flight attendants are just doing their job.

The great thing about international flights is that more often than not, the airline provides a free meal service. You usually won't be left to fend for yourself or shell out cash for overpriced junk food.

The bad thing about flying internationally is that there's a chance that you — or your kids, if you're traveling with them — won't like what's on the menu, let alone what might be left when the cart reaches your row.

Add in a potential delay, a sleepless night, and a long line at immigration, and suddenly you're on your way to a hangry meltdown. Play it safe and bring your own snacks.

On many international flights, free-flowing booze is one of the biggest perks, but if you aren't careful, drinking too much can put you on the fast track to dehydration and jet lag.

Also, be forewarned that people tend to feel alcohol's side effects more quickly on planes, as low humidity can cause dehydration, and low cabin pressure can decrease blood oxygen levels.

Sometimes people who down more alcohol on flights than they're used to can end up embarrassing themselves, their families, and their colleagues. Even worse, their behavior can land them a spot on the evening news or get them escorted off the plane.

If you're drinking, pace yourself and mix in plenty of water to stay hydrated.

The entertainment options on international flights tend to be a considerable upgrade from the offerings on domestic flights, with loads of newly released movies and premium TV series.

You should have no trouble wiling away the hours, as long as you bring headphones you can plug into the seat.

The flight attendants usually hand you a free set of earbuds. The only problem is that they're not always the most ergonomically sophisticated.

In my experience, the complimentary headphones can quickly go from uncomfortable to downright painful.

The climate onboard an airplane is very dry with low humidity levels due to the high altitude and outside air circulating in the cabin.

You may barely notice the dearth of moisture on a domestic flight, but when you're onboard for a long-haul trip, the desert-like air will suck every last drop of hydration from your hair, skin, and lips.

Don't forget your lotion and lip balm.