If you are traveling with your pet, it is usually not necessary to use a professional carrier, unless you are shipping an animal of unusual size or with special needs.
However, you made need help with pet transportation if your animal is taking a long jourey. You may find that airlines require you to employ a "known" shipper. This is part of an FAA security rule that applies to all cargo, not just animals.
The shipping company will work with you to compile the information required by the Transportation Security Administration and the US Department of Agriculture. At the time of shipping, you will be required to provide a current rabies certificate. You will also have to have your animal examined by a vet no more than 10 days before flight, and provide a health certificate before your pet can be accepted for shipping.