Teaching new things is hard. AFAIK there's no driver re-education program except for PSA's/news (i.e. headlines "new laws drivers must follow starting Jan 1"). For example the 3 ft law and how many people still don't know about it. A booth at the local farmer's market (assuming you can set up a booth inside the parking spots) is a way to educate/advertise. Online education is another avenue.
IMHO the most important part is patience. Any change takes 3-6 months for people to get used to it, and if they only use something once a year, that means to reach even half of the local populace you're looking at 1-2 years to first exposure. I have no idea how to get the idea into city council members' heads that every unique installation like this needs at least a 12 month "cooling off" period where people can get used to it.
Signs on the side of the road are the only real lasting mechanism. It's not great (who reads signs anymore?) but is an ever-present reminder.
Pre-education campaigns could help too; Bringing up small design features like this in places like facebook and nextdoor. Even if people reply with objections, they will have read it and understand how it's supposed to be used.
Any education effort takes time and money.
- Kevin