Dealing with acrophobia (extreme fear of heights) requires a lot of concious effort. Since the problem itself usually starts from the mind, whatever solution I will have something to do with your mindset. Just as you would put in efforts at learning methods to stop whatever you no longer want, same it is to dealing with acrophobia.
The first thing to do is to always prepare for the situation, once you know you have this irrational fear of high places, and you might encounter such as you go out, take a concious effort to prepare your mind for it, with time the irrational fear will disappear.
Another thing is, always visualize success at every encounter with high places, know that you can achieve success and you should know this is a slow process, you don't achieve it suddenly. Taking a deep breath always when you find yourself in high places will also help stop the irrational fear.