Start by identifying people who are great content providers and people who are good people managers. Assign them tasks that focus on their strengths. Content creators should be encouraged to create content, so keep their gritty management tine down, and people who are good at managing conflict and people get to be the faces of crises moderation.
Do not reward users with moderation power. Not everyone can handle power. Reward them with badges, button, titles, something that says "this person is a respected voice here."
Train people in verbal conflict resolution. Train them in the tools of the community. Have clear guides for when those tools are used - and have checks and balances, so no one individual moderator can ban or block with abandon.
Someone has to watch the watchers. Do performance reviews and know who is doing well and not so well. Don't let things get to crisis level, because you didn't know Moderator B was hacking and slashing your community up.
Have a clear hierarchy, clear community rules, clear processes for complaints and appeals and have a backup for yourself when you need a break!