Bruce Lee Hot Air Balloon
You start the flying process by laying out the balloon parts on the ground. Then one of the crew members (Bruce Lee in this case) holds open the mouth of the balloon while another member fires the burner into the envelope (first we use a fan to partially dill the balloon envelope before we start the burner). Yes, it gets warm, the burner is a 400,000 BTU device.
Once the envelope starts to heat up, the balloon starts to stand up. Once its fully erect we hold down the basket so the pilot and passengers can get in.
Just a fun picture here. At a Balloon rally in Denver Colorado, the balloon teams just inflate the balloons and run the burners (enough to stand up but not fly) to close out the days activities for the crowd. "Energizer Bunny" balloon on far right.