By the end of the month I will have done three roundtrips. Some advice:
Get to the airport early. Personally, there's not much more stressful than rushing to the airport, through security, etc.
Unless you get the nod, yes, laptop out of the bag and all metal objects out of your pockets. Drink your drink before security, too. Wrist watches don't seem to trigger the machines.
They're not really going to feed you in flight, so come prepared.
Everyone there--TSA, flight attendants, etc.--is just doing their job. Generally if you're nice to them, they're nice back.
When flying through Atlanta, there's a good chance you'll run into Ed Senf, dyno tuner to the stars.
Try to have a routine so you're not looking for stuff. I always keep my boarding pass in my right-rear pocket.
I love picking my seat before the flight. I'm a fan of the aisle. Bonus points for an exit row and/or bulkhead. Of course I get my free bumps to first class right before the end of the year, and come January 1 that privilege is gone.
If it's late and everyone around me is sleeping, I don't turn on the overhead lamp. Call it a general courtesy.
I try to time my pee break before we begin our initial descent so I don't have to go while we're stuck on the tarmac.
Headphones--even $30 ones--plus an iPod can make the time melt away.
I once helped Brian Redman put his bag in the overhead compartment. "Thanks for helping an old man with his bags," he said.
Also, I fly Delta a lot. Their Amex card gets me free checked bags on every flight. I travel with a backpack and a camera bag, so I'm usually checking my clothes. Knock on wood, it's been a long time since I have had a bag issue.