"Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did do. So throw off the bowlines, sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover." Mark Twain
And that is why I was going to Australia on my own in 2004! :-) However, mr Twain didn't mention those butterflies in the stomach... In hindsight, the trip was honestly the best thing I've ever done!! :-)
The most important things to bring on a holiday: The camera. The travel diary. And the passport and credit card might also be useful.. ;-) I also try to bring the phrase "I am vegetarian" in the local language.