Discuss the 12 agile principles and pick one to work on Source:
Print the principles of the Agile Manifesto onto cards, one principle per card. If the group is large, split it and provide each smaller group with their own set of the principles.
Explain that you want to order the principles according to the following question: 'How much do we need to improve regarding this principle?'. In the end the principle that is the team's weakest spot should be on top of the list.
Start with a random principle, discuss what it means and how much need for improvement you see, then place it in the middle. Pick the next principle, discuss what it means and sort it relatively to the other principles. You can propose a position depending on the previous discussion and move from there by comparison. Repeat this until all cards are sorted.
Now consider the card on top: This is presumeably the most needed and most urgent principle you should work on. How does the team feel about it? Does everyone still agree? What are the reasons there is the biggest demand for change here? Should you compare to the second or third most important issue again? If someone would now rather choose the second position, why?
If your boss had witnessed the last iteration, what would she want you to change? Source:
Imagine your boss had spent the last iteration - unrecognized - among you. What would she think about your interactions and results? What would she want you to change? This setting encourages the team to see themselves from a different angle.
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.