I fortunately haven't had to deal with this yet (haven't been far out the gate yet and all my other sailing was on the placid waters of the east coast), but almost looking forward to it! Then I'll be a genuine ocean-going sailor.
In any case, during one of the Strictly Sail seminars -- " are you prepared to go offshore? ", or something like that -- either the speaker or an audience member (can't remember) swore by this formula which he uses when taking new sailors offshore:
moderate dinner, then for breakfast the morning of your ocean adventure: 1 entire sleeve of saltine crackers and a liter(?) of water. No more, no less. Must finish it before you're allowed on the boat. He tells the crew to meet him at the best breakfast place in the city, and that he's picking up the tab (to prevent cheaters from filling up on greasy stuff beforehand). Then they all stand outside in their foulies eating saltines and watch jealously as people enjoy their omelettes and pancakes.
Use at own risk.