I see that you have gotten so many useful advices.
Most of my dives are boat dives, some are spacious, some are chaotic.
Maybe I can add few more things:
1. If you haven't finish gearing up, don't clog in the way of those who have. Let them pass so they can jump into the water first, especially if they already in full gear and standing with the heavy tank.
2. Don't leave your tank unsecure, it could fall on people toes/stuff.
3. Diving in Asia, usually people will help as much as they could. You can hand them weight belt (make sure you secure the weight with weight stopper, or hold it the way that the buckle is below so that weight wouldn't fall).
Sometimes they ask you to take out your BCD in the water too, while they fish them out. Make sure they hold the valve by positioning yourself right. It's extra service and it's very comvinient to climb into the boat just in wetsuit, especially for ladies or boat with steep ladder.
4. Do not steal other people's weight. Here, we don't have our own weight, we always use the ones provided by the boat. Sometimes, when we are preparing for number x dive, you realize that one or two weight can be missing because someone decide they need another one and it's easier to take the nearest available. If you need more weight, ask the boat crew for extra.
5. If you have similiar equipment with others, especially you don't put tag/name/worn out. Make sure you always put it in the same place to avoid confusion.
Cheers!
