If i were you i would check some past topics/ threads on this website before posting the question as there's a lot of information regarding working legally in China. Have you any idea that for first timers, you have to get your work visa at Chinese embassy in your home country? If your employer / school asks you to come to China with L (tourist) visas, that means they are NOT legit. Simply put, they DO NOT have the required papers to process your foreign expert certificate and hence work visa. Consequently, they are not allowed to hire a foreign teacher. To be forewarned is to be forearmed.

All the best.

BTW - I'm an academic director of an offline2online school and i've been in China for 15 years.