Hello,
Before trying to convince him or anyone else, please convince yourself that you have a better control over your anger.
The first step to solving any problem is the recognition of the problem, which you have done. The next step would be to seek help. The pertinent question is, where to seek help. The professional which can help you in learning the skills of anger management would be Psychiatrist or a Clinical Psychologist. Hence please seek an appointment with any of these to get a comprehensive assessment and management of these issues. The possible causes of anger dyscontrol, as well as situations, and other attributes will need assessment. Thereafter management can be done.
Anger control skills can be learnt with good motivation, practice, and a good therapist.
Hope this helps you. Best wishes for your health and future.
Next Steps
some of the commonly employed anger management skills are as follows-
1. Maintaining regular sleep, wake hours
2. regular meal times
3. avoid substance like alcohol or other substances
4. regular physical exercise to give an outlet/ vent to physical energy
5. better communication in relationship to avoid pent up negative feelings
6. use of stress balls or punching bags
7. leaving the situation of anger for some time
8. counting fro 1 to 100 and 100 to 1 forward and backward at times of impending anger
9. drinking a glass of cold water at such times
10. pursuing a hobby
11. better time management
Hope this helps you somewhat.