Don’t delay collecting feedback

Your Telegram-chat comes in handy at this stage, but you can also collect feedback in person. Print out small questionnaires in advance, hand them out to guests before the official end, and ask them to fill them out.

Make a board for feedback (it can be sheets of wattan with a heading), and leave felt-tip pens and pens next to it. It’s low-informative, but people like it.