**What to do:**
* Eat well, but don't overdo it. A hearty meal the night before and a solid breakfast the morning of the ride are a must.
* Stay well-hydrated.
* Get plenty of sleep. If you've been burning the midnight oil lately, cut back on your riding and catch more z's.
* Feel free to ride, but go for less distance and intensity than you normally would.
* Lube your chain (and clean if needed).
* Check your tires for any debris like glass or wire that might work it's way through during the ride.
* Top up the air in your tires.
* Check that your brakes still work properly.
**What _NOT_ to do:**
* any high-intensity rides or workouts
* another century (disregard if you normally do centuries on a regular basis)
* major mechanical changes to the bike
* any bike fit adjustments
* buy new shoes
(Assuming you've got the base training in already, of course)