In engineering, we usually have Handbooks that pretty much dictate the state of the practice. These books are usually devoid of theory and focus on the applied methodology. Is there a forecasting Handbook out there? that solely focuses on the technique and not the background?
There are two that I know of:
- Handbook of economic forecasting. Relatively theoretical. Not for undergraduates. A narrow look at forecasting --- specifically about economic forecasting.
- Principles of forecasting. Simpler, broader. Widely used by forecasting practitioners. Often reflects the idiosyncratic opinions of the editor which are presented as established facts.
Alternatively, you could use an intro textbook. My own textbook is often used as a sort of handbook by forecasting practitioners working in a business environment.