In the past two years I have travelled a lot, mostly for work.
I used to get hugely stressed at the mere thought of travel. I've had to learn to handle this, and I have. While I still don't always like it, travel doesn't really stress me anymore.
The biggest help in this change was the checklist. I wrote one for packing, and have extended it to the whole trip. This was the single biggest step for me. I no longer worry whether I've forgotten something. It helps that I know what I need to do every step of the way.
I've put a sample checklist on my website. You're free to use it as a base, or invent yours from scratch. The checklist needs to be adapted to your situation, and you need to keep it up to date.
Part of my routine is to create a new folder for the trip. I call it
something like "
Travel: 2009-07 Debconf9 and karmic sprint"—this
naming style happens to fit well into my archive folder. After the trip
is over, I move the travel folder into the archive folder.
I then copy the travel checklist into the travel folder, and edit it. I add contact information for hotels I'm going to stay in, and particularly important people I may need to reach if something bad happens.
The checklist has a superset of all the things I may need to take with me, and I trim that down to the necessities for this particular trip. For example, if I'm going to Spain in the middle of summer, I won't be needing winter clothing. I may need to add something, such as tools or equipment for something I need to do during that trip.
When it comes time to pack, I just follow the list, and I'm sure I won't forget anything.
The travel folder further gets digital copies of tickets, boarding passes, hotel reservation confirmations, and other such things. This makes it easy to find them, and easy to print them out.
The other big thing I've learned is to travel light. The big inspiration for this was the onebag.com site, which I highly recommend. It is not always possible to travel with only a single carry-on bag, but leaving behind anything that is not strictly necessary makes a big difference. The point is not how much you can bring with you, but how little.
The onebag.com site also taught me to pack well. Being limited to one bag requires packing things so they fit into the bag, without being crushed.
Finally, while on the road, I have a system for keeping track of my stuff. In my travel bag, I have a pocket where I always keep important papers, such as tickets, boarding passes, maps, and the printout of the checklist. Wallets, phones, passports, etc, go into specific places in my clothes. While on the road, I always know where every important thing is.