The purpose of a luggage tag is to help you and your luggage stay together while traveling. Use the first name initial and last name. Preferably use a business address rather than a home address. No need to advertise an empty house. Use a cell phone number, not your home phone. If no one is home, what use is a home phone number?
Buy a sturdy luggage tag. Suitcases go through a tremendous amount of abuse by the baggage handlers. Tags get torn off. Get a tag with a metal ring so the hole won't stretch or tear easily. Get a luggage tag that is easily identifiable. Pick one in bright or unusual colors so you can recognize it from a distance.
All carry-ons should also be tagged in case the bins are full and items need to go underneath. This includes child car seats, strollers, and diaper bags. You may also want to consider putting a tag on small children that includes contact information and destination.
