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 would make the next iteration a perfect 10 out of 10? Source:
Prepare a flip chart with 2 columns, a slim one for 'Rating' and a wide one for 'Actions'. Everyone rates the last iteration on a scale from 1 to 10. Then they have to suggest what action(s) would make the next iteration a perfect 10.
Gauge participants' satisfaction with the retro on a scale from 1 to 5 in minimum time Source:
ALE 2011, Corinna Baldauf
Put sticky notes on the door with the numbers 1 through 5 on them. 1 is the topmost and best, 5 the lowest and worst.When ending the retrospective, ask your participants to put a sticky to the number they feel reflects the session. The sticky can be empty or have a comment or suggestion on it.