you should send an invitation letter specifying the relationship between the applicant and his/her relative in China and duration of stay, the copy of your Residence Permit and your passport data pages, your mom need prepare the following documents:
1. her original passport
2. one passport photo
3. fill in one visa application form
4. relationship certificate

If all required documents are prepared, you should pay attention to the consular districts of Chinese embassy or consulates in India, if your mom live in the consular district of Chinese embassy in New Delhi, she should go to the Chinese visa application service center to apply for Chinese visa. For more information, please refer to https://www.travelchinaguide.com/embassy/india.htm