The best way to teach digital literacy to 1st graders would be at the beginning of the school year during the first few weeks when all the other protocols and rules are being established. The students need to know that technology a big part of the school's motto of being Kind, Respectful, Responsible and Safe. Before the students are even allowed to touch an ipad or chrome book the teacher would model appropriate digital citizen behavior. Scaffolding strategies would be an essential part of all lessons.
After the lessons were taught I would put them in partners and they get the opportunity to record each other following the correct way of the kind, respectful, responsible or safe lesson of their choice. This way they would get the chance to practice and have a little fun with it.
Lastly I would revisit the lesson after long breaks away from school like Winter recess and when a new student joined the class.