Explain an example of Value Stream Mapping. (If you're unfamiliar with it, check out this video or this printable 1-pager.) Ask the team to draw a value stream map of their process from the point of view of a single user story. If necessary, ask them to break into small groups, and facilitate the process if they need it. Look at the finished map. Where are long delays, choke points and bottlenecks?
Divide a flip chart into boxes headed with 'Start', 'Continue' and 'Stop'. Ask your participants to write concrete proposals for each category - 1 idea per index card. Let them write in silence for a few minutes. Let everyone read out their notes and post them to the appropriate category. Lead a short discussion on what the top 20% beneficial ideas are. Vote on it by distributing dots or X's with a marker, e.g. 1, 2, and 3 dots for each person to distribute. The top 2 or 3 become your action items.
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.