1. They worry too much about their guitar skills and not enough about their teaching skills.
Far and away the most common reason why someone stops going to see a guitar teacher is typically voiced like this:
"They sat there showing me all kinds of amazing stuff that they could do on their guitar, but I came away having learned nothing myself"
Yet when I talk to people who are considering starting out as guitar teachers, they are inevitably concerned about their own perceived lack of musical ability or comprehension of music theory; never their lack of teaching skills or experience.
One of the main reasons it is so easy to set up as a guitar teacher and become really successful at it, is that there are so many people out there doing it really badly. They're not doing it badly because they are bad people they are doing it badly because they make the assumption that it is all about being a great musician and seem to completely miss the point that it's actually about being a good teacher.
2. They overteach
When someone is paying you by the hour it is very easy to fall into the trap of thinking that you must be seen to be doing something to earn your fee throughout the hour that is being paid for.
Skilled teachers however, know that the doing must come mostly from the student. When I run 3-day courses on guitar teaching, the first exercise I get trainee guitar-teachers to complete involves sitting in front of a guitar student and doing nothing at all. It is, at first, an extraordinarily difficult exercise for people to do properly!
The point is that students need time and space to take in what you have asked them to do, to repeat it enough times to get it into muscle-memory' and to satisfy themselves that they have really got on top of it. While all this is going on, the very kindest thing the teacher can do is sit back in their chair and project the sense that they are happy to wait patiently for as long as it takes. And the best way to project that, is to do and say nothing other than to quietly observe the student's progress.
New teachers though, have a nasty habit of sitting forward on the edge of their seat, making all kinds of remarks intended to encourage the student, gesticulating with their hands and even the worst of all crimes - attempting to solo over what the student is playing for no reason other than because they cannot feel comfortable just to sit and observe.
3. They underestimate the range of differences in learning rates
I have seen quite a few posts on various forums about guitar teaching that recommend a particular way to teach a first lesson on guitar. Many of these ideas appear to ignore the harsh truth that there is a vast difference between the learning ability of different individuals who take up guitar.
I have had students never having played before, successfully improvise a blues guitar solo by the end of their first ever lesson. But I have also had guys who were still trying to get a single clean fretted note out of the instrument at the end of that first hour. And I have taught people of every shade of learning ability in between those two extremes.
So the first thing I train guitar teachers to put into their lesson planning, is adaptability. Never make assumptions about the rate of progress that will be made by a new student.
After a few lessons you will get a feel for how fast or how slow to take an individual student over the jumps and through the hoops.
4. They don't allow enough time or enough repetitions
As a newbie guitar teacher, you are probably a hundred times more likely to attempt to teach too much, too fast, than you are likely to err in the opposite direction.
Sensible teachers consult their students. Are you happy with your progress on that tune/exercise/riff/lick/ sequence, or would you like to run through it another couple of times?
Almost always, I have found that students need, and want, to go over things more often than might appear necessary to the inexperienced teacher.
5. They don't take time to assess
This one is mostly applicable to teaching people who have already been playing for a while.
Someone comes to me for lessons and, regardless of whether they describe themselves as a beginner, intermediate or advanced guitarist, I will always spend the first 10-30 minutes assessing what they can and can't do; what they do and don't know and most vitally, what they aspire to.
There is little more irritating for a student than to work with a teacher who makes assumptions about these things.
Teachers who assume you must have learnt to read tab or standard notation, when maybe all you have ever done is learn by ear. Teachers who assume that you know the names of all the chord shapes you play when you have just picked them all up by watching videos of your favourite guitar players. Teachers who assume that you want to play in a band, when actually your main purpose is to use the guitar to record your own music on your home computer.
How to learn to teach
There is no shortage of help available online when it comes to improving your musical knowledge and guitar playing skills. However, it is less obvious where to go to improve your guitar teaching skills.
Before the inevitable plug for my website that I know you can feel coming, let me say that there is no better way of learning to teach than by well er teaching.
My first advice to anyone considering taking up guitar teaching for a living is to start teaching as soon as possible and to teach as much as possible. If you don't feel ready to charge for this service then that is fine. Give lessons to family members, friends, kids at the orphanage for free. You will rapidly improve how you teach if you take this advice and then after a few lessons, come back and read this article again and see if you are managing to avoid the 5 mistakes.
Loads more free articles, materials, helpful advice plus the largest guitar teachers' forum on the net, all available at www.teachguitar.com
Happy Teaching and Playing!