First of all, you should realise that sometimes friendship break because of misunderstandings. You should also understand that there could be any other reason that made your friend aggressive and it affected the friendship.
Your friend might have some trouble at home and could not behave well because of that problem. You should also think that it was not an intentional thing that forced your friend to have a quarrel with you.
Give him a phone call, or drop him a message through cell phone or email and let him know that you want to meet him. Also let him know that you do not want him go from your life.
When you meet your friend, make sure you keep you tone low and polite. Let him know what you felt at the time of quarrel and also make him realise that he is important for you.
Patching up a broken friendship requires you to stay calm and ignore negative things which will help in mending the friendship in a desired manner.
Making an apology is one of the most important and effective things that help in eliminating problems. Apologise to your friend by saying that you are sorry for making him feel bad.
Talk about good times that you have spent together which will help in easing the tension of the situation. It will also help in making things favourable and you will get your friend back.
Try your best to ignore everything that caused trouble to the friendship. Without ignoring, you will not be able to mend a broken friendship.
Let your friend know that he is very precious for you and that you do not want to let him go again. It will help in resolving the issue in a favourable manner.