What can I do before my next lesson to help my learning

I'd strongly recommend focusing on the following.  Try to make each practice session count as opposed to just taking responsibility for driving to somewhere you need to be.  Remember it's not the quantity of the practicing, it's the quality! 

Firstly I'd focus on moving off at traffic lights.  Often you prepare to go on green which delays the traffic behind you.  Think about getting your car ready to go on amber and actually moving off on green.  What else can you use to alert your that your light is about to turn to green?  Can you see the lights controlling traffic flow from other directions?  If so there's a high possibility that when these lights turn red, yours will turn amber/green.

Secondly I'd work on planning ahead.  This about the furthest point you can see and what's developing there.  Are cars braking?  Are traffic lights changing?  Is there a situation developing?  Are there parked cars?  Is there oncoming traffic?  All of this information will help you plan ahead.  Remember if a situation is stressful, when driving, it's likely you didn't see it developing in time.  The fault is almost always a planning fault as opposed it a fault dealing with the situation.

Routes you may find useful to work on

I think Experienced Route 7 will really help you focus on your forward planning and judging meeting situations (parked cars)