Website: Establish a relationship with journalists, politicians, etc. or goupr with thousans of members adn once in a while ask them to share something from your site or social media and you do the same. In fact you have to do first in most cases.
Social Media: Create one Image with nice quotes about a profession for example Nurses, Doctors, Fire Fighters, journalists, and professions with huge number of members, then post and share them in their groups (social media, etc.)
When you post a video clips or an image or a news and noticed that they are getting more attention and likes Pin them for a day or if needed more in case of video clips