The below is an except culled from my own (internally) previously published material. I have to agree with much, if not most of what has already been presented here.
EXPERIENCE is the most important facet for all transfer of human learning.
Thus, the most important requirement for any trainer is solid foundation in the skill or knowledge they claim (or wish to gain) proficiency in. I know a lot of cats who THINK they can shoot...and the reality is, they really can't, because they do not have a clear understanding of the (shooting) fundamentals, and don't understand how consistently adhering to fundamentals provide consistent results. These would be the folks that talk about how "different" or difficult it is to move from shooting a "1911" to shooting a "SIG/M&P/H&K/Glock/Revolver". Pistol (or rifle) shooting fundamentals are just that. It does not matter if it's a two stage trigger or a 11lb trigger.
A good instructor should be able to positively motivate the student candidate from first contact. In general more learning can, and will take place if folks are highly motivated compared to not being positively motivated. This means that attitude, appearance, demeanor, hygiene and environment presented by the instructor play a crucial role in enhancing the (a) student’s mindset and thus motivation. Much of this transpires before the instructor has formally introduced him/herself. Unfortunately, many of the courses I have participated in (from the perspective of being a student or in the audience), the psychology and physiology of learning are not presented until the tail end of the presentation...and instructor trainer classes often recommend these portions are presented after the general body of information is delivered to the student.
It is not everyone that shows up that wants to learn...but it would certainly help if you had the tools with which to motivate them towards that end.
For ADULT students, trainers must also be able to present the new material being introduced to the student, in such a way that there is some association with some existing knowledge the student already has. This will allow for fast(er) assimilation of knowledge and skill.
Trainers must also constantly reflect back to when they were learning a (the) skill or assimilating new information. Too many of us forget how difficult it was to learn what we now construe to be rudimentary tasks (example, locking the action on a semi automatic rifle open). Since basic shooting is very skills dependent, an effective trainer will attempt to, as much as is possible, ensure that much of the instructional method incorporates hands on exercises, and if possible, “teach backs”.
For instructors of beginning students, it is critical to cover the fundamentals of shooting without attempting to impress new shooters with skills beyond the scope of training. I have suffered mightily thru classes being regaled with tales from trainers about scenarios and circumstances that did not reinforce the course objectives.
All the best!
ps - PAX, I sent you a private message back in December 2010. I'm jhoping you'll get a chance to peruse it, and assist me if possible.