If drivers will percieve the message of your campaign, so will pedastrians .
Contrasting colour combinations ensure that your campaign will stand out in the visual noise of its surroundings.
Less is More
The main message should not contain more than 7 words and a simple font is recomended. Remember that most of your audience on the move so keep it short.
Mind the colours of season (e.g. use bright colours during the wintertime when it's mostly grey weather)
Avoid using elements in the layout that could take away attention from the main message of your campaign.
Most importantly be brave & creative to get your fair share of attention!