I would recommend against using a tanning bed. They should be banned. They will greatly increase your chance of getting skin cancer.
I would go with a waterproof sunblock with a decent SPF, and one of those special lotions for the face. The intensity of the sun is particularly strong these days due to thinning ozone. And if you're in the water it will reflect off the surface and be that much worse. Just lather yourself completely and then you don't have to worry about it. When i snorkel i wear a tshirt or a scuba shirt. I would also consider a hat with a brim that gives you good coverage.