My preferred method is a sprinkling of firelighters in the base of the tray, a covering of lumpwood charcoal, and then charcoal briquettes over that. Pour half a cup of petrol over it all, leave for 2 mins to soak in, wash hands (to remove any petrol) and then chuck a match on.
The theory behind it is that the lumpwood is easy to light but doesn't burn for very long, so the lumpwood effectively "lights" the briquettes, which burn for about 2 hours.
What does everyone else do?