The first meeting that prevents most of it

Spend the first meeting on four things and nothing else. What exactly are we producing, written as one paragraph. Who owns which piece, by name. What each person's interim date is. And where we communicate, in one place, so nothing important lives in a chat somebody has muted.

Write it down and send it to everyone the same day. It is unglamorous, takes about forty minutes, and is the single highest-return act in the whole project. The group that skips it is the group that discovers in week five that two people have been writing the same section.