Move from the simple to the complex. Put examples in context to illustrate the use of the concept. What's the origin and purpose of the concept. Every body loves handouts. See Barb or me to get them copied.
Overheads are fine as are demos.
But don't spend time on powerpoint or any other presentation software. This is not a comps talk. Include references to your sources. Use a confident, interested tone. Direct the audience and not the board too much.