Oh crap, sorry! One more thing I did, I remember now. I clipped a Hue/Saturation layer to each of the "DODGE" and "BURN" layers, with the Saturation slider at +30 on the Master channel on each of those layers.
Then yeah, just paint as you see fit. Of course paint on the "Burn" layer where you want to darken, and the "Dodge" layer where you want to lighten.
This is what mine looked like: