It is important that the student and I set aims together and identify areas that they find more challenging, addressing these as a priority before moving on to topics that are less of a stumbling block.
Repetition is key to memorising and understanding concepts, so I would spend the first part of the lesson summarising and reviewing the previous week's topic(s) and perhaps working through one or two questions before progressing on to new content to ensure understanding.
With new content, I take the time to explain the topic to the student, encouraging them to ask questions whenever they feel the need to, before looking at a question together and guiding them through the necessary steps to achieve the correct answer.
At the end of the lesson, I make sure to give a quick summary, letting the student know what they did well in addition to what they could do with a little more work on. I agree with the pupil what the next lesson would entail, allowing us both time to prepare independently before the next lesson.
As we cover more of the course content, we will steadily move onto doing questions and past papers almost 100% of the time. From experience this is absolutely the best way to improve once the course content is learnt.