There is a lecture I give to many students one-on-one every semester when they get into trouble. It is about how to read a math book, i.e. basic study skills. I recommend it for all my students. How to read a math book.

A more recent lecture I have to give to lots of students is the one about dealing with being accident prone.

An alternative, and much longer, version, which I have not read myself, might be useful.

Something well worth looking at is the Mathematics Survival Guide.

This could explain a lot: Why Students Think They Understand - When They Don't.

A series of 6 videos on how to study

There are a lot of interesting things about learning on a colleague's website.