What to avoid.
Leave the pupil feeling that you were in control of the debrief. (The learner should be doing most of the talking here.)
Provide unrealistic feedback. (There is no benefit to telling the pupil everything was rainbows and unicorns when they’ve clearly been struggling for the last hour. Find the positives and acknowledge the learning opportunities. Even if the positives are just that you have uncovered a need for learning and you can therefore make progress.)
Rush the debrief, even if time is short (This can catch a lot of instructors out. You look at the clock and see you only have 1 minute left or the time has run out. So you rush the debrief doing all the talking or even just skip it altogether. The examiner would rather overrun a few minutes and see a nice conclusion to the lesson than have you ruin it all at the end rushing.)