You must first run a VASP calculation with LCHARG = True and LAECHG = True to run a Bader analysis. The former writes the CHGCAR and the latter writes the AECCAR files.
A Bader charge analysis can be run using the bader code by the Henkelman group (or even Critic2). It will tell you the charge on each atom.
Note that the Bader charge is the total charge per atom. To get something that is more like an oxidation state, you will need to subtract the number of valence electrons from the displayed charge value. This can be found in the POTCAR. For instance, if you run a calculation with the Br pseudopotential, you will see in the POTCAR file that it has 7 electrons treated as valence. Therefore, a Bader charge of 8.0 would indicate that the Br atom has a net charge of -1.
Using the Bader Code
The Henkelman group scripts will be available in your PATH on Princeton Research Computing machines after loading the VASP module.
To run a Bader charge analysis with the bader code, do the following:
chgsum.pl AECCAR0 AECCAR2
bader CHGCAR -ref CHGCAR_sum
The charges will be written out to a file called ACF.dat. You can delete the CHGCAR_sum file when you are done running the executable.
Using the Critic2 Code
The following uses Critic2 to do the Bader charge analysis. It should be very similar to the bader code.