Mathematics has given us the ability to perform complex calculations, reducing real world quantities to simple numbers and variables that can be manipulated without interpreting what they actually mean.
In your presentations, try to go back to the stage of a child before the first mathematics class. Describe measurements and quantities in a way that they can be visualized, internalized.
Recently, one of my presentations covered agricultural land yields in emerging markets. Rather than using abstract hectares and tons, I decided to use the soccer field analogy. It is easy to re-calculate figures from tons per hectare, to tons per soccer field, and maybe even going further: truck loads per soccer field.
You can even use the visual of the soccer field: