Thanks, Helen!
I'd say:
1. Break the topic down & sequence it so that you start with one simple idea that builds up.
2. For each lesson, start with a list of retrieval q's that check prior knowledge secure + use pupil answers to determine how much re-teaching you need to do...

3. Have a clear plan for your explanation for each lesson. I usually centre mine around key diagrams / bullet points that I draw under a visualiser. On the adjacent page hidden from the visualiser, I have a rough list of q's I will ask as the explanation proceeds.

4. The questions range from simple to complex; comprehension to application to ensure understanding is secure.
5. Plan the practice that pupils will do to help them independently think about the content. This means planning further questions for pupils to answer in their books.