Before I was diagnosed with stage III melanoma in August 2017, I used sunscreen the way I think a lot of people do: I applied it once whenever I went to the pool or beach, and then I’d sweat it all off and end up getting burned. I also played hundreds of rounds of golf over the years, but never once thought about applying sunscreen.

I’m a pretty outdoorsy guy and I grew up playing sports. So, it’s hard for me to limit my time outside...