The other point I'd make is that I went to grad school, and frankly in the technical subjects the professors are rarely the best coaches. Most of them have not been beginners for a long time, and their primary focus is not on how to relate to beginners. (Primary focus: How to relate to funding agencies. Secondary and tertiary focuses: How to relate to the rest of the department, and how to relate to grad students. Somewhere down near the bottom of the priority queue: Relating to undergraduates. Those profs who are primarily focused on teaching are absolute godsends, but are probably also having trouble getting tenure; such is the nature of undergraduate technical education at elite universities.)

The best coaches tend to be slightly-older fellow students. Ironically, the social structure of undergraduate classes is designed to segregate students at different levels of experience; the moral of that is: You must take steps to seek out older students who are willing to offer advice.