1) NEVER sedate a dog for air travel. Sedation can interfere with control of body temp, and makes it more likely your dog will have an issue.
2) Sky kennels are called sky kennels because that is what dogs are shipped by air in. It's smart to permanently attach the pieces, zip tie the door shut, and use cargo straps around the middle and length of the crate. When you have it done up this way, it sort of looks like it's wrapped with ribbon like a present. This ENSURES the crate will not come open during flight or handling.
3) make SURE your dog is very comfortable in a crate, and views it as a safe place before shipping time.
4) before shipping time, freeze water in a bucket to hang in the crate. Keep it in a cooler and frozen until they take the dog into baggage. This way it will thaw gradually and not be all sloshed out by the time they load the dog.
5) Put a brightly colored sign on top of the crate that reads something like:
My name is __________, and this is my first flight. I may be scared, so please speak kindly to me and handle my crate gently. Please do NOT put my crate on any moving conveyor belt. I appreciate being kept in a sheltered area out of the (cold/heat/sun) if possible. Wags, and woofs, (name of dog).
this gives the dog a "personality" and an identity to those handling him, and almost guarantees he will be spoken to by name when he's being handled on the ramp.
6) Insure the dog for NO LESS than 10,000 US. This is not expensive, and I PROMISE YOU it makes for a difference in the way the dog is handled.