Are you flying in the near future? If you are, you may want to now how to get a free airline upgrade to first class.
To increase your odds, you should sign up for the airline's frequent flyer program. You're going to find that if you want to increase your odds at nabbing a spot, a frequent flyer membership will help tremendously. These are usually free, and can found on the airline's website.
When booking your trip, consider flying out of a smaller airport. If you fly out of a major airport, you will find that most of the flights are going to be full. Your goal is to hop on a plane that isn't full.
Before you head out to the airport, dress in a business casual outfit. Airlines like to have nicely dressed people in the first class section, trust me. This will increase your odds as well.
When you show up to the airport, ask the clerk at the counter that you want to be on the waiting list for first class. Tell them your name, and give them your frequent flyer number. Remember, be nice!
Now, it's the gamble. Your name will either be called, or maybe it won't be. Just sit back, and wait.