Timing is a big deal in the process and Lu can guide you through that. The paperwork/vaccinations have to be done in a specific time frame (not too early and not too late). If I recall correctly, the paperwork included:
-HK license
-Rabies vaccination card
-Other vaccination card
-Health certificate filled out by vet
Space for your dog as "excess baggage" is NOT guaranteed. Before you purchase your ticket on Cathay, you need to confirm there is space for your dog. Then the actual price will not be calculated until you arrive at the airport and your dog/crate are weighed. Cathay will not fly flat-faced dogs (i.e. pugs, bulldogs, etc). United will.
Suggestions:
-Before the big trip, leave the crate in the house so the dog can get familiar with it. The day of the trip should not be the first time the dog is closed in the crate.
-Buy a large drip water dispenser - like the kind hamsters drink from and teach your dog to drink from it. He will not automatically know how to do it. This is the most reliable water supply as any sort of dish will splash out.
-That said, I still clip a plastic dish with frozen water (so it doesn't spill) on the crate door the moment before handing over the dog to the airlines.
-Leave a t-shirt in the crate so your dog has your scent to calm him. Do not expect the t-shirt to survive the trip. Good chance your dog will soil the crate. -Carry a collapsable bowl on the plane so that you can give your dog water from the drinking fountain immediately after he's brought out to you near baggage claim. He'll be very thirsty.
-Airline will want you to zip-tie the door of the crate closed. I didn't want to do that because you cannot open the door without a knife or scissors. In an emergency, you need to get that door open ASAP. Instead, I used a plastic clip (or you can use a tiny, keychain-type carabiner) on a cord to secure the door shut.
-Have a set of paperwork attached to the crate. Carry a set on you as well. I even have a set scanned and available on a thumb drive and attached to an email I can access from any internet connection in the world.
-Attached a picture of your dog to the crate and his name.
-Be a pain . . . tell everyone in a uniform on the flight that your dog is on board. Have the flight attendant alert the captain.
-Have a strategy for after the plane lands. The crate is too big for most trunks. Do you have a van coming to pick you up? The dog will be likely be filthy; are you set up to give him a bath? Do you have the name/number/address of a vet nearby just in case?