Often, anger is alerting you to a particular problem. One thing to do then is to solve that problem. If you are routinely finding yourself angered by being stuck in traffic, find an alternate route or leave a little earlier or later when there is less traffic. If you are frequently frustrated by a computer program that doesn’t work the way you want it to, find a better program or work with your IT people to make that program work better.
Whatever the solution, the point is that dedicating a little time to solving the problem is better than letting the problem frustrate you day in and day out.