Start with general conversation, to get the student re-acquainted with English.
Then move on to more in-depth discussion, regarding a pre-determined topic to-be-decided by the student, something that they are interested in at the time. (news topics, work situation, hobbies, etc.)
I tailor all my lessons around the student's English level, their perceived weaknesses, and future goals. The aim is the student to increase their confidence in communicating with others.
Rather than using textbooks and books, I believe that communication levels can be improved by immersing someone in the language, in a topic that they are highly interested in.
Although I am billingual, I will speak English only in the lesson.