Create a histogram on how well ritual meetings went during the iteration Source:
Prepare a flip chart for each meeting that recurs every iteration, (e.g. the Scrum ceremonies) with a horizontal scale from 1 ('Did not meet expectations') to 5 ('Exceeds Expectations'). Each team member adds a sticky note based on their rating for each of these meetings. Let the team discuss why some meetings do not have a rating of 5. You can discuss improvements as part of this activity or in a later activity such as Perfection Game (#20) or Plus \& Delta (#40).
Let team members appreciate each other and end positively Source:
Agile Retrospectives who took it from 'The Satir Model: Family Therapy and Beyond'
Start by giving a sincere appreciation of one of the participants. It can be anything they contributed: help to the team or you, a solved problem, ...Then invite others and wait for someone to work up the nerve. Close, when no one has talked for a minute.