Iranian people need to overwhelmingly decide to do it
The issue with this is that it's terrifying for the vast majority of people to try and resist a murderous autocratic regime, especially when you're not sure if enough other people in your vicinity will (successfully) have your back to make sure that you're not kidnapped and tortured or shot right in the street.
Ideally, we should have an international nonviolent organization that could arrive wherever needed to help a population get out of the shackles (with no strings attached)
The problem is that the people at the top don't want informed citizens. There should be a citizenry(?) class through 3 years of high school, and there should be a sort of public access channel (including online) that disseminates all relevant political information (local and general).