There are many effective ways to complain about online training teachers. Here are some common methods:

1. Contact the training institution directly: If the training teacher teaches in the training institution, you can directly contact the person in charge of the institution or the personnel department to reflect the problems to them and ask for treatment.

2. Online complaint platform: Now many websites provide online complaint platforms, where you can fill in relevant information, describe the content of complaints, upload relevant evidence and submit complaints. Such complaints are usually dealt with in time.

3. Report to relevant departments: If the training of teachers involves violations of laws and regulations, you can report to relevant departments, such as education departments and human resources departments.

4. Seek legal aid: If the complaint is serious, you can seek legal aid, seek the help of a lawyer and solve the problem through legal means.

However, before complaining, we can also try to communicate with the teacher to see if we can solve the problem. If it can't be solved, consider the complaint again. At the same time, we should also keep relevant evidence, such as chat records and videos, for future use. Finally, it is necessary to treat complaints rationally and not be overly emotional, so as not to affect the efficiency of solving problems.