Microbuses from Coban leave in late mornings; schedules change every few months (~3 hours, depending on road conditions). There are also buses that leave from Santa Cruz del Quiche; the last bus leaves in mid-afternoon (~3.5 hours, depending on road conditions).
Ask for recommendations in the Municipal Tourism Office on the central plaza. Hikes are available to local waterfalls, the developing ecotourism site where Rigoberta Menchu was born, and Uspanteko (Maya) rituals.
Two popular choices are Casa Blanca, which is at the entrance of town coming from Cunen in the south, or Dona Leonor, which is located just two blocks off the central plaza.
Buses from Uspantan leave every 30 minutes beginning at 3:30 until 7AM from the central plaza to Santa Cruz del Quiche. There are also microbuses, schedules change every few months.