A very easy technique to make a pic look glossy is to duplicate it and then you must select the upper layer and add gaussian blur and set the radius at 15 px. Then you must set the upper layer mode to either soft light or overlay. But to make a pic more lighter you can repeat the above steps but instead of overlay or soft light you must use screen. This will add a bit of spotlight. When it's too bright add the Dodge tool and dodge the parts you want to be less bright