Well, professional photographers genaerally use a light sourse that incides from a diferent angle that the lenses. Or a difusor. If you use a reflex camera with a atachable flash, turn the flash slitly upwards, and use a difusor if you have one. If you use a digital or regular camera with attached flash i think it might be better to get a lamp in a 45º angle to the subject you are shooting, then turn the flah off. If you have a macro option, even better, but be sure to read in your manual how far should you be at least (mine is 0,5meters) don't stand too close or your camera won't be able to focus, it's preferable to zoom in to get a close up from that point. To avoid fuzzyness of the picture you might want to secure the position of your camera, if you don't have a tripod don't worry, almost everything will do. I sometimes use a bag of rice underneath the camera. Then hold your breath for a second, press and voilá! Your should have a beautiful close up of your even more beautifull recently created nails!