The Bryce Canyon Visitor Center should be one of your
first stops when visiting Bryce Canyon National Park. You can acquire
driving and hiking directions, weather forecasts, a current schedule of Park
Ranger guided programs, and information on area services.
One of the most interesting Ranger programs takes place
during the three days closest to the full moon in summer and fall. You
can take a 1 or 2 mile moonlight hike with a ranger. It's a
fascinating adventure. The tours fill up quickly as they are limited
to 30 people and reservations are only made available the day of the hike.
If you don't make it into a ranger's group, you can always hike by yourself.
I've done that several times and it's been quite rewarding.
See NPS site for more details