Getting stuff wrong...
Many believe boating to be a contact sport and accept the odd 'bump' as a right of passage. If you do bump into another boat, simply smile and say sorry - most boaters will know how you feel, may make a slightly cutting comment anyway, but will let it go and probably smile to themselves after you've gone whilst remembering the time they did exactly the same thing.
On very odd occasions you'll find a grumpy and thoroughly nasty old/young git who'll like you to think they've never made a mistake in the history of their boating career, and they may try to give you a pretty hard time. Again, smile, say sorry and pass in peace - you will hardly ever see such situations develop into anything more serious than a few heated words - please do not match 'like for like' if they start to swear or shout at you - just smile, stay calm and say sorry - they then have many other options other than to accept your smile.