I play position 3,4,5 in SEA and have coached students from all brackets - helped Divine players hit immo and archons hit legend. I always note down all comments with an emphasis on the most important for you to work on. I like to teach in terms of principles and rules so that it is easy for students to follow, for example: the golden rule of support during the laning stage is harassing or pulling (or stacking), you have to be doing 1 of these 2 things at any point in time during laning in order to have impact.