#1
How would I go about doing this? If I just tuned it like I would if I was going for regular D tuning, would it work? I've heard you can do some tricks with the fine tuners, like have the screw all the way at the bottom then unscrew it all the way to the top?
#2
If its a big change, unscrew the locking nuts and tune there, and use the fine tuners to get back after many moons have passed that a locking nut looses its tuning (slightly).

It is possible that you can make a big change by using the fine tuners, but this will result in "the guitar throwing the tuning out and not going back in for an hour", says my guitar teacher.
#3
Quote by Banana Wedgie

It is possible that you can make a big change by using the fine tuners, but this will result in "the guitar throwing the tuning out and not going back in for an hour", says my guitar teacher.

been there... don't do it...
as for drop c, tune it and adjust the springs in the back cavity of the guitar so the floyd is parallel to the body
i tuned from e standard to drop d with just the fine tuner but it screws up the whole tuning...(i tune e>d, everything else goes a tone higher), the more you try to tune it locked, the worse it gets...
MY GEAR:
Digitech RP250
Stagg Acoustic
Ibanez RGA32 (EMG 81/85)
amp doesn't matter :P