Project with senior-level stakeholders.
Congratulations - you've been given a major project with senior-level stakeholders.
Now what?
It's all about communication.
Make sure everyone is kept informed. How you do that and how frequently will depend on the audience and urgency.
Communicate effectively. See my recent post on Keeping It Simple &Straightforward: KISS.
Personalize the message. I usually keep a larger ppt deck handy but personalize the message for every audience interaction.
All of these things I learned from experience. I have been lucky to have some amazing managers who did this really well!