To get started watch the three videos at:
Although when using the phone, the design flows, as a software designer, architect or engineer knowing the basic concepts of the Windows Phone design concepts is important.
At the end of the three videos you should have a good idea of how the Windows Phone Metro design functions, and the motivation that drives the Metro Design.
Also did you notice that there are a number of ways to navigate, none use physical buttons but rather focus on the use of gestures.
Read the following Steven Sinofsky blogs, even though they are mostly words and long, you should take the time to read them: