What types of static image posts are working to create hype for in-person events?

Hi there, fellow SMM - 

I manage social for an SaaS in the risk management space called Riskonnect and we’re wondering what type of out-of-the-box static image posts that are working well for your brand to promote upcoming in-person events and virtual webinar type events. 

We have no trouble getting engagement on in-person event posts when we’re live at an event, but it’s pretty challenging to get quality engagement on posts leading up to an event (not posting about events is not an option). 

Thanks in advance for your ideas/suggestions! -Katy