When you’re ever going to do a day of supply teaching make sure you take your ID.
You will generally always be asked to take photo ID, so that’s your Passport or Driving License.
Along with ID you will always need your most recent CRB, make sure you take the right one that the agency your’re on supply with, will have a copy of.
When you arrive at the school you will be asked to show your ID and CRB and asked to sign in the visitors book. If your’re in a car you will probably need to know your car registration number as well.