Besides what we all talk about, booking another one right away, or as Lil' Lori says, even before she gets off, try finding your "cruise saturation point"; that's the point where you actually start to look forward to going home.
I know some of you doubters will say, "there is no such thing!"
You just haven't been on a long enough cruise. For some it might be 7 days; for others it mihgt be 30; but we all have one--except you world cruisers--you are hopeless cases.
Mine is about 15 days. At that point I've had just about enough rich food, dressing up, dressing down, changing clothes five times a day, rocking in the shower, standing in line, toilet jokes and hyperactive cruise staff. I'm ready for a jar of peanut butter and a romp with my dog.
And I also hope you can all see my tongue planted firmly in my cheek.