Help Wanted - Deciphering Crochet Pattern

[nezchan.livejournal.com]

I'm pretty new to crocheting, but I really want to try this pattern. The trouble is, I'm not sure I fully understand it.

Actually, I'm fine right up to where it says "Continue following pattern", where I get confused. Why do I chain 829 if the pattern itself is only 280 wide? Is the only stitch involved DC? I don't really get it!

Obviously, I need help. So in the absence of a therapist, I want to figure out how to crochet a dragon. ^__^