There's many choices you have to make when you're traveling; many things that could go wrong because of your decision or choice. But there is one exact moment after which nothing you do, arrange or decide affects your travel, and that's after you've passed through the security check at the airport. That's when nothing can go wrong any more. I just passed through 10 minutes ago.
The decision that worried me the most was how to get to the airport. One option would be to cycle to the airport and bag the bike on the spot. If all goes well, that's by far the easiest and cheapest option. But also the most risky. You could have a puncture on the way, you might not know if your bike will fit in the bag, or how to bag up all your panniers. Also, since you're packing your stuff in the unsafe area of the airport you risk getting robbed. The actual risk of this depends on which airport you're flying from, of course.
The alternative is to pack everything at home, which means you now have to choose if you're going to use public transport or a taxi to get to the airport. Public transport was really not an option for me, as it would involve two transfers, and the London underground is way too tiny to comfortable transport a bagged bicycle plus a massive bag full of luggage. And, as it turns out, today there was a tube strike, so it wouldn't have worked anyway. The last argument against public transport for my particular case was that I would have to walk 10+ minutes to the station. That's just something you can't do if you're carrying a bagged bicycle and 20kg of luggage.
So, a taxi it is then. These are crazy expensive! At least in London they are. I found various offers online varying between 45 and 75GBP to get to Heathrow from where I live. You'll have to pick whichever one seems reasonably value-for-money (I couldn't possibly use the word 'cheap') and also trustworthy. As for the latter criteria, none of the taxi companies seem to qualify, so a little chancing and faithing is involved there. If you choose this option, your immediate next worry will be if the taxi will actually show up in time and if you can arrange an alternative in time should that happen. Once your driver does show up your final taxi worries will be the traffic and if the driver will try to scam you at the end. In my case the driver turned out to be a nice guy who arrived much too early, which was good since the tube strike caused massive traffic and it took a good half hour longer to get to the airport.
Arriving at the airport, almost nothing can go wrong. Almost. What if British Airways really did only allow me one check-in bag, even though the website said I could have two? (Yes, I worry a lot..) Then comes the horrible moment of weighing the luggage. If you've prepared properly you already know how heavy it is, but you might be pushing the limits a little in which case you might have to repack. In my experience airlines tend to be insanely strict about the weight limit, but will often let you take part of your luggage as an additional carry-on item. Once you've done that (and asked for the appropriate 'fragile' and 'do not stack' stickers) it's off to the oversized baggage drop-off. There's never a problem here, though if you're unlucky your baggage handler may seem like a person who enjoys inflicting pain on luggage. Don't worry about that though, since there's nothing you can do about it (except complain afterwards if they break something).
Lastly, the security checkpoint. This is when you usually remember about that water bottle, massive tube of toothpaste and giant swiss army knife that you forgot to put into your check-in bag. Oh well. Once you've cleared this minor hurdle you're done! No more decisions you make will affect the quality of your journey from now on. All you have to do is sit down, relax and enjoy the ride.
(/me practicing blogposting again! I'm a little rusty..)