courtesy ? 'on your left !' lol
make sure you are hydrated - before and during the ride
for some water (alone) is sufficient - others might prefer a sports drink (instead or combination) - since you have trained for this ride you probably understand what works for you
some will not require solid food - others will need solid food (again you probably know what works for you) ... might want to bring energy bar(s) or whatever if you don't want to depend or chance it at the rest stops
make sure your tires are properly inflated (I preferred to ride a century or similar on fresh tires with just a few rides)
have fun and good luck !
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