Put in front of people, let them read it and have them highlight in green/red the parts that they understand (or make them confident or whatever your goal is) or not.
Follow-up with "why" people describe things as helpful or unhelpful.
This goes back to Associations between concepts is thinking: You want to uncover which parts of your content trigger helpful associations and which associations are perhaps missing altogether for people to understand.
Ask what people expect to happen next – uncovers expectations within a flow.