This is what i have found.

  (Edited: ) This guy, Filter is a very good person to begin with. He goes through the basics with you and does a series called "Bronze to Masters." it has helped me just power through the ladder and helps to serve as a refresher later on[9] talks about mechanics and doing a simple build in order to get good at doing one thing here. He says that if you do this, you will be able to quite easily get up there and start becoming a better player.

This last one i would recommend for you once you start branching out and want to round out your play. dApollo is an excellent player and caster and will no doubt help you to improve