keeping signature cotton clean?

  1. does anyone know/have any ideas on how to keep the signature cotton bags clean?
  2. The SA's in the Coach boutique told me to use unscented baby wipes or a cloth with mild soap and water. Do not use the Coach fabric cleaner.
  3. How often would you recommend wiping it down with those baby wipes?
  4. My assumption was to spot treat as needed. It didn't occur to me to actually wipe the whole bag down. Hmmm, maybe I will give my Coach boutique a call.