Have fun?
One thing I didn't realize when I was training is that you don't have to be doing the distances you will race at in your training. It's not bad to do them (or even more) but it's not necessary. I was thinking that, since I was going to bike 13 miles, swim 1/2 a mile and run 4 that I needed to be swimming 960 meters, biking 15-16 miles and running about 6. But it turns out that you only need to train about 90% of the distance, not 110-120% like I was thinking.
I'm not sure why that is, but I did my first Olympic (.9 mi swim, 26 mi bike, 6.2 mi run) when I'd never run more than 5.5 miles and that was with breaks (it was a track workout) and had only biked 23 miles tops and only one time and I was fine. I think it's because my total mileage for the week was over what I raced and, to your body, it's not *that* much different if you are doing it over a week or over a day.
The other thing is: watch some transition videos on YouTube and PRACTICE! You'll feel so much better on race day if you aren't fumbling around in transition trying to figure things out.
Oh and don't be one of those people who brings an entire suitcase into transition. :svengo: It's going to be tight in there so, even if you bring a lot, just lay out what you need and put the rest back in your bag or your car.