We all have different units and checklists, procedures change from rebreather to rebreather and no one will tell you how or when to do your stuff. On the other hand, we do require that you participate and do OUR way in the following aspects:
You have to have a checklist of your unit available at the place where you assembly your rebreather. At some point before EVERY dive, pre-breathe the unit and participate in a panga ABC cross check before entering the water. Once in the water you need to participate in a bubble check and team member count.