Within my company in our QRH we have some CAT II/III guidelines (yellow pages) where we go trough before any CAT II/III approach.
Here is a short Copy/Past
PRIOR TO OR DURING DESCENT
CM1 is PF.
Check airfield facilities status (CAT III RWY, Notams,...).
Check aircraft STS page & table of requirements (A/C malfunction).
Press / check Autoland warning annunciators.
Determine applicable minimas (States minimas).
Check / Set “NO” in DH box on MCDU “PERF APPR” page.
Review approach / missed approach and go around procedures. Review airport low visibility procedures.
Review CM1 and CM2 call-outs during APPR.
Review procedures in case of malfunction during APPR:
Refer to FCOM PRO-NOR-SRP-01 FMS Approach (Failures and associated actions).
We press and check it with the LS option ON to see the LOC/GS scale blinking. And we do it on both sides (CPT and FO).
It will most probably one day save your ass as EcamSurprise stated.