I'll share the checklist that our 6.0.3 deployment team used last month..
- Energy drinks
- Sleepless night
- Pizza delivery booked
- Coffee & doughnuts
Are you launching a platform? a community? is it a virtual launch?
I would get a checklist together of everything you expect to work post install from day 1 - mail routing, connectors, Office tools, http redirects, embedded html, any and all features and functionality you expect to demo and test, test, test.
Make sure you regularly restart the system, especially post any config changes.