I think I am a good dive buddy because I am always turning around looking for them making sure they are close by. I also ask about their air often, so they are never in dire need of surfacing. I point out things I find, I always take photos of them too! I help them with their gear before we dive and check things together. If they have a problem while diving, if they are done, then I am done too.
Of course, my silly jokes are really the best part of diving with me! lol