The two other posters pretty much breaked it down.

But I would like to add an analogy that might make you see what needs to be done.

To tell yourself to not get excited is just as difficult as telling yourself to not be nervous when you approach a girl or public speaking.

The reason to the problem is that it's new to you. When you hammer it down over and over you will eventually reach a point where it is normal to you and you will no longer get excited, or for my other examples you will no longer get nervous.

In most cases it's not about doing something, it's about being something.

However in order be something you need to change something that you do.

But what I mean is that you don't need some special fix or method to solve this problem, all you need to do is to continue to experience this excitement over and over, until it's no longer there.

Good luck!