It is reported that this city has successively rain during this period. So, take some warm clothes such as thin sweater and rainproof shoes.
Actually, this city does not has too many excellent attractions. However, the suburb counties and villages around Guiyang are full of wonderful sceneries and ethnic groups. For the details, please refer to: https://www.travelchinaguide.com/attraction/guizhou/guiyang/
You also could find some hotel suggestions there.
Transportation, don't expect too much for the city's public transport. Most of travelers will rent a cab with drivers for long excursion.