Give a visual image
The human mind is immensely powerful when it comes to visual images. That is why, when you are providing your concluding remarks, it may be a good idea to show an image to your audience that pertains to your point.
While it may be easier to include this strategy if you are presenting a PowerPoint slideshow during your discussion, there are surely other ways to do so. Consider what kind of image relates to the aim of your discussion and would be useful for your audience to see before they leave. What will help cement your message in their minds?
You may use this method to communicate a time-sensitive message by displaying a running timer. The timer will emphasize your concluding statements and motivate your audience to act.