The first time I rode in a balloon and shot I was very apprehensive but I quickly realized it is a very calm, quiet ride that makes photographing very enjoyable. Hopefully you will get the opportunity for this exhilarating experience to give a different view to your images.
A few suggestions that I would offer as I have learned from experience. Take equipment that you can handhold because there is not much room for a tripod. When I have been in the balloon there have always been several occupants. If you are alone with the pilot there would be more room. Take at least two lenses, one being a wide angle and the other a telephoto so you can cover all possible views.
The photos in this post were taken around Walla Walla, Washington during the annual balloon stampede which takes place on the second weekend of May each year. Visit that festival and you will be entertained by the color of the balloons as well as the beauty of the Palouse region.