Great answer from @Jim Haviland42! Only thing I would add is less non-profit specific and more about looking at your Accountability Chart. By looking over each person's roles, you can think about "How will I know if they are succeeding or failing in any one of these roles" on their seat. Those ultimately become your Scorecard metrics.
On our team we had everyone come up with at least 5 for their seat, brought them all to a meeting and then talked about which ones we thought were important enough to keep as our Scorecard. It's evolved over time but I still thought it was a good exercise to get started.