It's easy to get up early in Bali for some reason, maybe it's the roosters. There are a few things on the Ubud sunrise activities list – meditate at home, scooter in to town for yoga class (Intuitive Flow have an incredible one where you see the sun rise over the Campuhan Ridge), pick up fruit at the Ubud Markets, scooter in the soft, golden light or walk the Campuhan Ridge.
The Ridge Walk is no secret but I've never actually seen it crowded, it's long and meandering so there's room for all to wander. After 9am it starts to heat up in the full Bali sun though so sunrise is a good time to visit. The young Balinese locals call this place 'Bukit Cinta', translated, Love Hill, so you can always spot a teen couple or two walking hand-in-hand, in love, along the walk which adds to the atmosphere.
Take the path to the left of Warwick Ibah on Jalan Raya Campuhan and keep left