1. Collect evidence: First, collect all the evidence related to your suspicion, including chat records, payment vouchers, contracts, etc. Make sure the evidence can support your accusation.
2. Contact relevant institutions: According to your contact background with Mr. Xu Kui, determine which institutions you can complain to. It can be schools, education departments, relevant associations or organizations, etc. Before you complain, you must understand the complaint process and requirements of these institutions.
3. Submit the complaint: submit the complaint, relevant evidence and other necessary materials to the relevant institutions according to the requirements of the institutions. Make sure the complaint contains specific allegations, evidence and your contact information.
4. Follow up the complaint: Once the complaint is submitted, keep communication with the organization and provide any additional information or evidence in time. Follow the organization's procedures and wait patiently for their investigation and feedback.
5. Seek legal aid: If you think that Mr. Xu Kui's behavior is illegal, you can consult a lawyer for legal aid to determine whether you can take legal action.
Please note that the above suggestions are for reference only, and the specific complaint procedures may vary from region to region and specific circumstances. It is recommended that you further consult relevant institutions or professionals before complaining to ensure that your behavior complies with laws and regulations.