My only thought regarding the hourly wage would be to look at it in comparison perhaps of the $$ that you could make if you played poker for that hour, plus an adjustment bump for taking a fish out of the game that could lower your future earnings from the game.
So for example in 2/5 if your beating it consitently for say 10bb/100, well live we all know if you get 50
hands /hour your doing ok so you would be looking at 25$/hr that you are loosing out on by coaching rather than playing. Just based on this you would want to charge 25$/hr min and perhaps adjust to that x2 for your involved time, effort knowledge sharing and improvement of their game (ie the coaching aspect). Just a thought on a quick and dirty way to look at it, as well as taking into account that via coaching you are generally teaching them how you think in terms of the game and therefore potential of no longer making $$ from them at the times or at least not as much as you once did if you both play at the same limits (which given 1/2 is generally the lowest live you would)
My suggestion would be make yourself out a plan, does he want specific coaching or overall start to finish improvement of his game, does he recognize leaks in his game he needs specific help with or do you perhaps know these from playing etc. You want an action plan so you know where to focus and to stay on track given you havn't tought/coached before. As a player we focus but also have many thoughts going through out head, as a teacher we need to be focused and have particular organization of the thoughts and actions we will be taking or we could go off track and confuse the student more.
Think of it no different than if you were doing a course in college in a way, basically first thing you get in the course is an outline of what you are going to cover. This is the instructors plan for the length of the course, sure other topics may come up and be looked at but these are the key necesarry items that have to be covered to meet course requirements. This is no different, as the student to your coaching they should also have expectations of you with regards to the plan of action.
Just my thoughts as of now, might be a little disorganized but hope not too much so for you to get the point I am trying to make with it all. Personally I think coaching another player would be a great way to improve on your own game as well, if nothing more than to strengthen the fundamentals, as it is going to involve much thought as to what you will be discussing etc prior to actually starting the coaching. Also example based scenarios work well to back up theory etc, as too many words without pictures is very uninteresting most of the time and could lose the student and cause them to get nothing out of the coaching (being at fault of both parties).
Good Luck with it.
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