I didn't heed the warning. I tried to tan my pale Celtic skin, over and over again, to the point of blisters and lobster-red skin. On the days when I wasn't trying to burn myself, I forgot sunscreen.
I had a mole removed a few weeks ago. It was "congenital but with a number of abnormal cell divisions," which basically means I was born with it but due to my failure to appropriately protect it (and the rest of myself) from the sun, it was pre-cancerous. I have to go back in six months and every year thereafter for the rest of my life, because once you've had one mole like that, the odds are greater that you will have more cancerous or pre-cancerous moles.
So, wear sunscreen.
**I was, in fact, part of the class of '99. That song was even DIRECTED at me and I didn't listen.**