How to become less aggressive in my behavior?

The goal here is to engage as you are trying to do in Anger Management which takes awareness and practice. It is also important to consider that there could be other symptoms associated like stress, anxiety and depression  that need to be addressed. It is also important to understand what is motivating such strong emotion and impulsivity leading to loss of control. You also may have low frustration tolerance and be more easily triggered than others, so knowing yourself and your personal triggers is important.

• To begin with, you would benefit from recognizing the signs that you are becoming upset. So you might for example experience the following right before: rapid heartbeat, faster breathing, tense muscles, restlessness, clenched fists or jaw sweating and pacing. Be aware of this onset so you can implement coping skills to try to avert an episode.
• Simple relaxation tools such as deep breathing, using relaxing imagery, can help calm down angry feelings.  You can also "walk away" if you feel you are on the edge and take a personal "time out" until the feelings pass.
• Cognitive restructuring is another technique which means changing the way you think. Angry people tend to think in exaggerated and dramatic terms. Try replacing these thoughts with more rational ones. So instead of telling yourself things are "awful, ruined, terrible" tell yourself "this is frustrating but manageable and it is understandable why I am upset, but I will get through it and it is not the end of the world".
• Use consequential thinking.  For example, reflect -"when I lost my temper last time I got into a fight and got arrested. I do not want this to happen again so I will....." and plan your strategy.
• Remind yourself  that getting angry and losing your temper will not solve anything and instead will make things worse.
• You also have to practice these skills when you are not angry so you are ready if and when you feel you are losing control.
• You can also join an anger management group and receive psychoeducation and peer support. You can also go to talk therapy and learn more about your relationship with anger and its origins in your life.  
• In regard to taking action that is helpful, you can learn to practice verbalizing your feelings and needs in an assertive but not aggressive way so you are heard.  Being assertive does not mean being pushy but instead clear and respectful while speaking in the "I" and not attacking the other.

These are all things to consider and remember logic triumphs over anger.  I hope this helped!