Does anyone know how to successfully set up OnPartialUpdate

I currently have an app where the screen will invert to where the background is white and the text background is black.  I think it is due to me updating everything every second in OnUpdate().  So other devices may have trouble loading it.

Does anyone know of an example Watch Face that implements a good version of OnPartialUpdate? As well as if someone knows about the color inversion issue, I would love some feedback on the issue.