The basics are simple: There are three types of CFI ratings, essentially "single-engine," "multi-engine," and "instrument!"
It is truly the one license that perpetuates the whole cycle of flying. Instructors teach new people to become, what instructors already are: Pilots!
In my years as a flight-instructor (or "CFI"), the biggest challenge I faced was not teaching the mechanical aspects of flying, or the understanding of weather concepts .... it was the passing on the skill of "good judgment."
The old adage is, that one arrives at making good decisions by having made many bad ones before, except that in flying a bad decision can have tragic consequences.
So I begin and carry on instructing by building many scenarios exercised both in the air and on the ground, helping you recognize and meet challenges head-on, instead of having them sneak up on you.
The "big" training issues are different along every step of the way:
A private pilot trainee (unless previously trained for a sport-pilot license) has to absorb a whole new dimension, a realization that "pulling over to the side" is not an option, and that -in the end- you are the pilot who has to make the tough calls in the best interest of safety
An instrument-student faces other issues: The pilot is flying in and actively participating with a very complex Air Traffic Control system with very concrete requirements and expectations.
The multi-engine student encounters the common fallacy that two engines -despite their redundancy- are not always safer. Proper training will ensure that the redundancy in systems translates into improved safety, whereas wrong actions will have a bad situation deteriorate even further very quickly.
