My first scrapbook was a WDW trip.....I started by dividing my photos by subject and day (my album is semi-chronological).....arrival, our hotel, different things in each park, parades, character meals, etc....
That gave me my basic order for my album. I did write a list of pages I wanted to do in the order I wanted them....like this
Arrival/WDW gates
Wyndham
Playmobil
Race Rock
Polynesian
Main Street USA
Cinderella Castle
Adventureland
Breakfast with Pooh
you get the idea.....some of the subjects above were just one page and some were several pages....and there were lots more subjects.
If you are intimidated by starting on your cruise pics, grab some old pics you're not really worried about and do your first pages using those. It's a confidence booster.
You have been given lots of great advice! One more thing...don't forget to work your memoribilia into your pages. I'm terrible at forgetting to do this...then the memoribilia ends up homeless.
Most of all, Have Fun!