"Now, rig for women's head."
On my sailboat, when my lady guests felt the need to relieve themselves, I would simply place a funnel into the centerboard well, so the lady could kick a leg over the well and straddle it, thereby discharging directly into the sea.
The command, "Now, rig for women's head" alerted the gentlemen aboard to look away for modesty's sake.
Typical centerboard well installation on a small sailboat
Gentlemen, of course, simply hung it out over the side to leeward while firmly gripping the leeward shroud. (Never, ever to windward.)
"One hand for the ship, and one for yourself."