So you must decide on the main points you want them to absorb. The salient points of your teaching can be covered in recaps at the start of the next lesson, and overviews of what has been learnt at the end of the current lesson. The two or three main points you want them to remember need to be memorable, so your lesson planning must be tightly focused, and you must be aware of the key items in your lessons. As well as the broad sweep of the lesson, you should also try to develop a range of strategies to highlight those key points to the pupils.
For example, stand up to stress a point. Or develop a phrase to signpost an important point - a colleague of mine uses the phrase "Flourish of trumpets!" Or you can use noise or visual triggers - knock the blackboard, clap your hands, or lower your voice.
At some point, write the main points on the board, but remember that pupils will be writing all week, so don't assume that their writing things down all the time will do the trick. You are looking for hidden triggers to aid memory. It can be fun trying to find them, and then to use them without pupils realising.
Roy Watson-Davies is an advanced skills teacher at Blackfen school for girls, Orpington, Kent