So you ignored your girlfriend when she told you to apply the SPF. Bad move, Hellboy. Soak a washcloth in cold milk and lay it over your burn. (The milk creates a protein film that helps ease the pain.) Then apply a moisturizer containing hyaluronic acid, which will make it less likely to peel (try Dermalogica Ultrarich Body Cream, $47). Then pop some aspirin, which has been shown to reduce redness and other negative effects of a burn when taken immediately.