Honestly, it's going to be a cooperative effort on the part of the group, but it's also going to take some flexibility on your part as the GM.

I think the trick is to allow the players to keep the key events of their character's stories flexible enough that they can be folded into the greater narrative of the adventure being run.  And the designers considered this by allowing players to change what the next step in the story can be in case the step they chose turns out to be unattainable for whatever reason.

While the PCs are all stars of the adventure, they're also part of an ensemble cast, which means they're going to need to be able to share the spotlight, which means there may be times when their personal stories won't advance that session.  And that's okay, because by participating in the larger story (the adventure), they've still got opportunities for advancement outside oftheir personal stories.

The trick with quiet players and those who get overruled by the stronger participants is to aim the GM story to take the players to their story goal locations. Leave the running to far lands while ignoring plots for the players who will push the party there on their own. For the quiet ones, drop the hooks near what you have planned for the group. And do not shy from telling a player " your goal is far from what we are planning, it may take time to get to it" so they can reconsider their story plan. (You are also allowed to alter their steps to fit your plotting locations to am certain extent)