Before heading to the airport see if there is a lounge that will let you in. Whether through PriorityPass, Lounge Buddy, or your Airline or credit card Loyalty programme of choice.
Be sure of which terminal you are headed to. While in the vast majority of instances this is obvious, there have been some surprises. Oh, and once I went to a completely different (aka wrong) airport.
Always carry an easily accessible pen.
At check in: So very many places have online check in and/or airport kiosk checkin that this will be the norm. However, as you fly to more remote places, with airlines that are not plugged in to the international systems, you will have to physically check in on a regular basis. The latest iteration of the US passport has a much more rigid information page that works much better with scanners. So replace your passport if yours is older.
Pick the line with the fewest families and fewest macro stacks of luggage. Hat and sunglasses off for passport photo check. Have a screenshot of your visa approval open for viewing (an increasing number of countries tie the visa to your passport so it appears automatically). Have your COVID vaccination record at hand.
Have Tripit open to show the agent your ongoing flight to prove that you have a plan to leave the destination country. As discussed elsewhere if you do not have firm plans you can dummy this to appear in your plans with a reservation made and then cancelled within 24 hours.
Tighten the cinch straps on your backpack to reduce the chance that the agent will challenge your carryon.
If you bought some durables and are counting on a tourist VAT reimbursement, forget about it. The desks are often unmanned.
Departure tax. Most often included in the price of the airline ticket, but sometimes payable in cash. I smuggly approached security in Apia, Samoa for an international leg with cash in hand after paying the tax on a local flight the week before, to discover that only the small regional airline did not automatically collect it. Lots of snacks and big tips with my local currency.
Security screening: Much as the need to qualify and pay for TSA Precheck (included in Global Entry, but I maintain both) infuriates me, this is an absolute must have for flights originating in the US. It is nearly always the shortest line, with the fewest intrusive restrictions. But as it has become more popular make sure to review both pre and non precheck lines, and be ready to switch to regular security lane if it looks significantly shorter.
CLEAR programme. Yet another private org that has a copy of my retina. But it is expanding rapidly across US airports (and will doubtless be a regular part of office entry and concert going in the near future). This really speeds me through pre security lines with an ‘concierge service’ vibe. Some of the larger airports have a confusing array of options including ‘CLEAR non precheck’ and ‘CLEAR precheck’ lanes that may be not colocated.
As with check in, choose the line with fewest families and smallest luggage.
If any of your clothing has set off scanners in the past, gift it and buy new comfortable and smart items.
Judging from the bins full of water filled bottles a remarkable number of people are just not paying attention.
There are plenty of little Napoleons at security. Each has a set of non negotiable rules. Shoes on/off; laptop in own tray/or okay with ‘phone; ziplock of gels out/remain in bag? Look ahead in the line to see what specifics are enforced, and just do that. This is true of pretty much every travel inflection point. Keep your face out of your ‘phone to see what will be expected.
I have been witness to so very many protestations from passengers that ‘this was fine in XYZ airport’. These are futile places to make a stand. Whatever Security wants to confiscate from me I just say ‘your house your rules’. In hundreds of flights I have never had unmarked medication challenged. Or powders (laundry detergent). A small minority take away my tiny corkscrew. Occasionally my toothpaste is deemed dangerous.
Customs and Border formalities are getting broadly simpler. Many modern airports now have automatic service gates, in which you scan your passport and have your picture taken, and you are done. Smaller regionals still have manned booths but, with the exception of the dictatorships and highly militarized countries, most are pretty swift.
Take a stroll down to preview the departure gate. Because this can change, and the overhead announcements are infuriatingly impenetrable to me. I almost missed a flight in Singapore due to a gate change and muddy announcement. I then put the items I want for the flight (ipad, headphones, phone, book, cables, etc) in to my linen market bag so that when I get on the ‘plane I can stow my bag and sit down. And not be that guy who is unzipping and searching while the rest of the passengers wait behind him.
At boarding time I do not spend time concerning myself which of the dozen or so categories of passengers I belong in, or how soon I can get on the ‘plane. My seat is always waiting for me, and I have never had difficulty stowing my luggage. Since I have what I want for my flight in a market bag it doesn’t matter where my luggage is, as long as it is closer to the exit than my seat is. Board later than earlier if on a regional turboprop aircraft. The air conditioning is at best mediocre, and it will not be active until the engines are started.