Make sure that the student can give a focused, concise three-part answer to a question. There is no use writing too much at the outset of an answer, then running out of time to write the conclusion.
If you have any doubt about what is required, meet with your student's teachers for an explanation.
Help the student to study consistently according to a set routine. Information that is stored in the brain bit by bit, according to a daily schedule, is easier to retain that information remembered through cramming.
Give the student a quiet, comfortable place to study and provide plenty of support in terms of encouragement, food and forms of relaxation.