I am preparing for my first dive trip. My wife surprised me with a trip to Cancun, we leave Saturday. So I have very little time to prepare!
For those of you who travel to dive, what do you bring? What should you expect? What is proper for tipping on a boat dive?
Anything I should make sure I do NOT bring? Anything I should make sure I do NOT do (besides the normal ugly american things

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<edited by Larry>
This post brought lot's of good answers, and the original poster Doghouse was nice enough to compile the information gathered at this post: Packing for my first dive trip. Pls Help
Feel free to continue to add, and we'll update as needed.
Thanks to all the people who added their thoughts and comments.
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