The key elements of an effective security awareness program?
I'd start with the strategic goals and objectives of the organization.
An inventory of all of the organizational assets. Especially, the mission critical assets.
A list of laws, regulations, and standards that are applicable to the organization's industry and the data they keep.
A cybersecurity framework, a risk management framework, and a controls framework.
SMART metrics and measurements to set standards and targets as well as to measure performance.
But if you want something quick, tell the users to quit clicking on links in emails. That will fix most issues if they pay attention and follow instructions.