so, might as well go thru a few more important things...
well before the event/ prep 'training'...
if you don't already, always 'warm up' on the bike in the early part of every ride. I recommend 10 to 15% warmup time - 30 miler - 4 mi. warmup, 50 miler 6-7 mi warmup, 100 miler 8-10 mile warmup. sometimes a group ride just 'goes' from the start - so I always get my warmup before - ride to the 'ride', if driving, park some distance from the 'start' and roll to start (which allows a 'cooldown' ride back to car). Always do a 'warmup' and cool-down! 1st century ? Use the 15 - 20 min from the start as 'warmup riding'... There will be those who go full blast from the start - suffering is part of the cycling ethic... LOL! but you don;t have to experience that in your 1st 100... If you come to the finish feeling 'done' but not 'out', then you did it right. If you have to get a ride back in the 'Broom Wagon', you will be unhappy.
If you can, do a 'metric' (60-62 mi) 3 or 4 weeks before the full 100... it'll give you a feeling for how to do things and how you handle the ride.
Before the BIG event
the 2 -3 days before - do 'Small Ring' rides - easy pace, comfortable spin, at a pace you at which you can easily 'talk'... 45 min to 1 hr is fine.
morning of race - have your morning meal 2 hrs before the start - gives enough time to digest properly.
Finish of 100 - last 8 miles - steady, no heavy efforts, use the finish as a 'cool-down', your body will appreciate it greatly in the coming hours and days.
Have Fun! you might even make some new acquaintances and friends!
Ride on... some more...
Yuri