Hi CruiseBeginner, welcome to Cruise-Chat! Congratulations on your up-coming cruise! I hope you enjoy Princess as much as we do, they're our favorite line, so far. As you can see, we enjoy having fun on this board
A 3 day is a good way to get your feet wet, however, you won't get the total relaxation package because you'll be so busy trying to do everything on the Patter
Seriously, you can do as much or as little as you wish. If they have the International Cafe on the Sapphire (I haven't yet sailed her), be sure to try some gelato. It's 3 scoops for $1.50 and absolutely fantastic. They also have some free things available, pastries and such. Best wishes for a fantastic cruise!