Pamela Slim gives some tips:
# As soon as you get to your location, set up and test your equipment. Schmoozing, coffee and furniture re-arranging can wait.
# Check and double check to make sure you bring the right presentation, and right version of the presentation, to the live event. Am I the only one that does last-minute changes to a presentation and mistakenly saves it to the wrong place on my hard drive?
# Fully charge your laptop battery, and bring a backup if necessary, even if you are planning to use a power cord.