Gather the right people
Doesn’t matter how big or important the project is, someone is likely to be left out. There’s no reason to call the whole team for a kick-off meeting when the actual work is being done by two people. Anyone who doesn’t have a clear role, even your brightest talent, could become a bottleneck down the road.
Be sure to clarify who are you bringing in and why. Do it both for who’s in and for those who feel ruled out for no reason.
Set a clear purpose
Together works better when everyone knows what the desired outcome is. A clear briefing and definite deliverables are just the start - your team needs guidelines: shall they play by the book? Shall they be innovative? Is your goal a quick delivery? Is it high quality?
Even more important: your team must know what the consequences of a job well done will be, for the company and for them. Knowing all these things beforehand will ease up decisions all along.
Have a process
Once the emotional and practical guidelines have been set, you’d better think up a process. Since each team member is either the customer or the supplier for some part of the job, a process defines roles, streamlines production and lets everyone keep in mind who depends on who.
When everybody knows what should be done, they can really put in the hours dealing with the foundation of teamwork: solitary, deep work, solving the hard stuff.
Be a leader
All the steps above require a strong leadership, focused on goals and on relationships as well. Hard decisions will be taken, acknowledgements given, different perspectives negotiated. People will have their say - and if they don’t voice it up, they must be asked for it.
Leadership means sharing a view and asking others for feedback. A leader needs the insight of its team.
To avoid design-by-committee, however, someone should take the final decisions.
Just let the team know that.