Participants show how they feel by drawing a face on a tangerine Source:
Each team member gets a sharpie and a tangerine with a sticky note asking: 'How do you feel? Please give me a face'. After all are done drawing you go around and compare the works of art and emotions. It's a light-hearted way to set the stage.
Set up a 'retrospective mailbox' at the beginning of the iteration. Whenever something significant happens or someone has an idea for improvement, they write it down and 'post' it. (Alternatively the 'mailbox' can be a visible place. This can spark discussion during the iteration.) Go through the notes and discuss them. A mailbox is great for long iterations and forgetful teams.
What could sub-groups improve when interacting with others? Source:
Identify sub-groups within the participants that interacted during the iteration, e.g. developers/testers, clients/providers, PO/developers, etc. Give participants 3 minutes to silently write down what they think their group did that negatively impacted another group. One person should be part of one group only and write stickies for all groups they don't belong to - 1 sticky per issue.
Then in turn all participants read their stickies and give them to the corresponding group. The affected group rates it from 0 ('It was not a problem') to 5 ('It was a big problem'). Thus you get insights and shared understanding about problems and can select some of them to work on.
Prepare 3 flip chart papers titled 'Helped', 'Hindered', and 'Hypothesis' (suggestions for things to try out). Ask participants to help you grow and improve as a facilitator by writing you sticky notes and signing their initials so that you may ask questions later.