I usually begin with a taster lesson, where we cover multiple concepts from a low to higher level to identify and understand the student's weaknesses. From that point onward, each lesson would begin with a 5-10 minutes quiz to recap definitions or key concepts. The rest of the lesson would be dedicated to one topic I've identified as needing consolidation or that the student has asked me to cover. This would include introductions to concepts including me drawing diagrams, or working through example questions. Then we would tackle a worksheet on that topic, going through the questions together. I'll guide their thought process through the questions and try and nudge them to discover the answer themselves. If they feel confident by the end of the lesson I'll give them a few questions to try independently, that we will check afterwards. The lesson time would usually be an hour and I may give them optional worksheets to practice if it is necessary.