It's been 44 years since the original Slip, Slop, Slap! PSA campaign was launched on Australian TV and billboards.

https://www.youtube.com/watch?v=b7nocIenCYg

  Slip, Slop, Slap!
  Slip on a shirt, slop on sunscreen and slap on a hat
  Slip, Slop, Slap!
  You can stop skin cancer - say: 'Slip, Slop, Slap!'

Revised & updated in 2010: https://www.youtube.com/watch?v=FzA47J7QsVk