Freddy

Well, its entirely up to you. Some sunblock is acutally a good moisturizer, so you can apply it right after you should as if it were any other lotion and you cover your entire body evenly. If you want to go with the less drastic route you could just apply it to your hands and face. Remember though that suits are make of silk or wool and are often thick. You can't get away without wearing sunblock with a light white t-shirt, so this would only apply to thick clothing.