I love cruises. Get to your boarding early. If they say 1pm get there at noon. You will board early, while not waiting in line, and that's when you can get your cruise card. It's basically a credit card for the ship. They don't accept anything else onboard. Some cruise lines even allow you to tip out the whole staff through that card, although they prefer cash. You tip at the end of the cruise all at once in clever little envelopes that they will supply to you. I think having a little cash in pocket is always good, as the first couple of hours on board the bars are taking cash.
You can book shore excursions from the company's web site. If you wait it may be sold out.
Don't try to do everything, you'll tire out, I did the first time.
A little dramamine doesn't hurt, follow recommended dosage, and just have fun.
The biggest worry I had was not missing out on something, that's why I keep going.
Best, most consistent vacations I've ever had.
STogie