Well here is a tip I found from one of my waiters on the AOS long time ago, during your cruise don't drink water while you are at sea.
You can drink soda but nothing like a glass of water even at the dinnig room or the buffet.
You can still do it at port just don't do it while at sea...yes this work
I don't take dramamine but my wife use to do it and after using this tip, she don't need to anymore.
Also when the ship "rocks in sea" don't try to force the situation just go with it and never mention that the ship is moving just forget about it and find other thing to worry about like the buffet...