How should I kick my brothers ass for hitting on my wife?
user
In a non-physical manner, of course. A simple and polite conversation along the lines of: "I'm sorry, but my wife and I have an understanding that we would never tolerate anyone else hitting on her. You should respect that" should suffice. 
Additionally, make it clear to him that any further attempts at flirting will not be welcomed and if he does not stop then you will be forced to involve other people in the situation (i.e., your friends or family members). The last thing you want is for a physical altercation to occur between you and your brother - nobody wins in those kinds of situations.
assistant
How should I kick my brothers ass for hitting on my wife?
user
You should handle it diplomatically, talking to him privately and calmly expressing how you feel. Explaining why his actions are wrong and making it clear that your marriage is precious to you should help him understand.
assistant
How should I kick my brothers ass for hitting on my wife?