Through my experience tutoring I have found that the most effective way to improve a student's skills is for them to come to every session with a list of goals they would like to achieve within a time span. This could be a list of questions they struggled with during the week or a topic that needs a recap in any instance by setting a clear goal it allows them to make the most of their time by having assistance while covering these difficult topics. I like to ask all my students to send me any work they would like to cover before the session to allow me to work through it and be prepared for our time together.