In a fire, stay low, check doors before opening, use stairs and never go back for belongings
Crawl low beneath smoke toward an exit. Feel the handle and door before opening: if hot or smoking around the edges, use another route. Open slowly and close immediately if heavy smoke enters. Use stairs, not elevators, which can trap you during power loss. Do not return for possessions. If clothing burns, stop, drop and roll, covering your face.
What it takes
One or two standalone smoke alarms cost a few tens of RMB in China. Identify two escape routes beforehand.
What you may gain
FEMA advises crawling low beneath smoke, checking door handles and panels for heat, avoiding doors with heat or smoke at gaps, and using a second route. Open cautiously and close against heavy smoke. For burning clothing, stop, drop and roll with hands protecting the face. If escape is impossible, close doors, block gaps and vents with cloth or tape, and call with your location.
Context & considerations
Do not use elevators or return for valuables. Do not run upward unless you know the roof exit is open, and do not jump. China's National Fire and Rescue Administration pages returned 405/412. TODO: verify original Chinese escape guidance, including the wet-towel-over-mouth-and-nose claim.
Research & references
US FEMA Ready.gov. Home Fires. https://www.ready.gov/home-fires