I recently got an A/B A+B C loop switcher pedal (the black 3 button pedal) and another overdrive the RC Booster (not pictured). The Boss RC30 and MXR are both in my FX loop. The OCD, Fuzz and the RC booster are the ones I will use the switcher for, I plan to stack the OCD and RC Booster. The power supply will be put underneath the board. Any suggestions how should I arrange my pedals?

Ocd and AC off to the side and out of the way if your using them with a switcher. I always put high use pedals up front if possible to make it easier for my size 12 to reach its goal.
So Amp<Switcher< Fuzz<OCD<AC Booster (might have that backwards but that makes sense to me)

I would trade places with the power Supply and Footswitch might be easier to use that way.

Keep the RC and Mxr where they are. And keep them in your Effects loop (Duh)

Thats just me. Sorry if that doesnt Help. This is how i set mine up for Ref.

Amp<Digi Chorus<TS9<AD9<Tu2<Wah<Guitar
The Rig of Joy:
Stiff Amplification Dirthead 20w
Bugera 2x12 Cab
Fender Partscaster Korean Made
Epiphone Prophecy
Washburn Southern Cross 34 of 100
Ibanez TS9,AD9,GCB95, Multi Chorus and TU2