Explain how to interpret unfamiliar graphs before you show them
So what was the problem? The audience would have no idea how to read the graphs. And the entire message would be lost, or even worse, misinterpreted. I suggested that they start that section of the presentation by explaining to the audience how to interpret what they were about to see on the graphs. We enlarged one of the data values and explained what the data point represented and why the error bars were there. Armed with information on how to interpret the graphs, the audience would then read the graphs correctly.
If you have to present graphs that may be unfamiliar to the audience, make sure you first explain how to understand what they are about to see. It may be familiar to you, but those without your background will not understand what you are showing unless you first teach them how to read the graph.