Good advice from ethanryan. Try to keep calm (hard I know!) and as far as possible totally ignore him when he is naughty and smile and encourage him when he is being good - to the point where you feel like an idiot, but it will work. e.g keep up a contstant dialog with him. "that very good putting on your jacket, aren't you a good boy putting on your jacket like that - that's very nice walking, see how you are staying beside mummy and keeping safe etc etc". My younger son used to work out ways that he could have a tantrum - he would say black was white just so that he could get himself worked up - he still does sometimes although he is 6 and a half - finally managed to totally embarrass him by videoing him in full flight and showing it to him so that he could see how ridiculous he looked!
He would get down on the ground and bang his head of the concrete - he is not stupid though,once he realised that it hurt, he woud just do a convincing act but not actually touch the ground.
You are not alone - just keep at it and it will get better as they grow - then it becomes an advantage to have two as they play together.