Well it's all about the value of your post, and if I was able to predict how to trigger an emotion and increase the chances of people sharing every piece of content, then I would be a "richer" person, in more ways than one, than I am now!

So how do we get it right, most of the time?

Humour we all know works, however sometimes the content, or subject just isn't really appropriate for humour, so I think the same rules apply as they always have; try and create content that resonates with your audience, where people are likely to start a conversation and gain real value at a time when they need it.  

The challenge for marketers, and any content producer, is how to leverage social media, paid or earned, make the content accessible and not get lost in the myriad of exchanges that are happening every day.   

There are some great creative content providers, where structured advice can give you the essence of how to stay ahead!  Balancing all this isn't easy, however, we can all but try!!