I applied in-person. The process took 1 day. I interviewed at Stepping Stones (Shanghai, Shanghai) in Oct 2014
Interview
You go into the office and have a chat with the Director, Corinne Hua. She's very nice and speaks both English and Mandarin. She basically asks you what you're doing in China (as an expat) and if you have free time or not to volunteer your time to stepping stones. Overall it was a simple and effective process.
Interview questions [1]
Question 1
Will you be able to commit your time for at least one program a week