Nighttime is the time to be out in Guiyang. The city is a lot more attractive once the sun goes down and, generally speaking, has a better atmosphere too. Guiyang人 have a reputation for getting up/ starting work a bit late, and going to bed late too. As a result, its fun just to walk around.
Also good:
-Night market street food. From about 6元 you'll get some tasty stuff, and its more enjoyable than expensive restaurants a lot of the time.
- Coffee shops. Guiyang has increasing numbers of places that serve coffee.. some good, some bad, some just OK. I personally like the Createa chain (cheapish, busy, nicely decorated) and highlands coffee for its genuinely good tasting coffee (rare round here) and delicious cakes etc.
- river.. that area is pretty cool. Have a beer on at the pagoda (Jia Xu Lou.. can't remember the name) sadly they only serve "snow" which isn't the best Chinese beer.