1. Organize your ID/passport and boarding pass
Coming through a security check is discombobulating. Re-combobulate yourself and place your form of ID and boarding pass together, in a place that's secure but easily accessible. Give your gate number a glance and say it outloud before stashing that pass.
2. Fill up a water bottle
Even if you have to pay the exorbitant price of $4 for a bottle of water at the airport, it will pay off in the long run. Forget the torture of waiting for the service cart to reach your row just to request water. Bring your own! Consuming water throughout a flight (whether it's 2 hours or 12) means lowering risk of dry skin and jet lag while counteracting the saltiness of in-flight food.
3. Locate a power outlet and charge up your phone
This isn't always easy considering the scarcity of power outlets at airport terminals, but boarding a plane with as near a 100% charge as possible means you'll be able to enjoy your music and media in case the airplane's in-flight entertainment goes haywire (or it completely lacks a system). And, safety-wise, just in case something happens (like an emergency landing to a different airport from your desired destination), you'll have charge enough to notify those waiting on you.
4. Social media moment!
Waiting in line to board is a good time to do a final update of your social media networks. Refresh Twitter, Instagram, Facebook and whatever else. Check into the airport and flight number on Foursquare. We even like to plan ahead and check the Foursquare tips for our destination hotel, plus save some WikiTravel pages to our Instapaper app for offline reading on the plane.
5. Check to see if your upgrade has gone through
This only applies to those flyers with airline status and the way it's displayed depends on the airline, but for those depending on it for a good night's sleep or a hearty meal, it can be the most crucial part of pre-boarding.
US airlines tend to display the first three letters of the passenger's last name, plus first initial, in order of status on the upgrade list. Of course if it's not clear, check with the gate agent.
Got any other tips? Share them in comments below!
[Photos: Jaunted, triphackr]