Depends on audience/location.
Are they people who already ride for commuting? Then skip promoting riding a bike
In our case (a large university in a large city that draws from the whole state--and rural states to the west--and lots of foreign students). I'd teach basic traffic safety. I've found that many of the foreign students and many students from rural areas and small towns think it is OK (or were actually taught to) ride against traffic. Lots don't understand the dangers of riding the wrong way, don't understand the dangers of riding on the sidewalk, don't have a clue about being visible at night, don't know how to be predictable. Lots are listening the their music through earphones when riding. They don't even understand that most bikeways, unless marked, are one way.