Starting a big application with unit testing

I am learning test driven develeopment and read some books about TDD. I learned rules of unit testing. How can I write unit test, how can I select test method names, Act, Assert, Action and like this.

In real word I developed applications that have layered architecture. Domain Layer, Data Layer, Service Layer, UI Layer, ....

How can I start an application with TDD. Is there a rule or way or else. For example starting Service Layer.