Translating Territory requirements into a design
Before you can build your Territory Model, you need to define your types and hierarchy. Your hierarchy will typically have a geographical component and your types will likely represent the other dimension in your forecasting matrix, such as the industry vertical or customer size. You should aim to draw out your hierarchy before you start to build.
You also need to decide how you structure your assignment rules. You are likely to have geographically based criteria, perhaps by country, or for countries as large as the US, it might be by state or zip code. For this, you need to make sure that the data you are using is standardized and complete. If you have not done so already you should consider implementing the State and Country/Territory Picklists functionality. This will ensure you have a consistent set of data to use in the criteria. In addition to the geographical criteria, you will also have criteria that specify the other dimensions...