Yes, get your booking number from your travel agent. Go to the Princess website and fill everything out there. Book any shore excursions you know you want to as well. You will be sent your deiocuments already filled out and though it may or may not say express boarding on your tickets, there isn't a long wait. Also, you can board early on Princess. You can drop your hand luggage at your cabin, but then need to be in the public rooms until the usual boarding times.