If you have not already signed up for AdWords API, you can do so by going
here. While our compliance team reviews your application, you can
create test accounts and try making test API calls by
setting up OAuth credentials for test accounts in your favorite
client library. You can also go through
sample code examples to get a heads up on using the API. Once the application is approved, you can start making API calls against production AdWords account, the process for which is the same as test accounts. Once your connectivity with production accounts is up an running, you can download
reporting data from your account and display on your dashboard. If you plan to use Java language client library, you can optionally checkout our
AwReporting Framework, which can be used to sync AdWords reporting data to your local database, which in turn can be used to render on your dashboard.