Remind each other of agile values you displayed Source:
Draw 4 large bubbles and write one of the agile core values into each:
Individuals and their interactions
Delivering working software
Responding to change
Ask participants to write down instances when their colleagues have displayed one of the values - 1 cheerful sticky note per example. In turn, let everyone post their note in the corresponding bubble and read them out loud. Rejoice in how you embody agile core values :)
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.
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.