If your camera is on and won't show and pictures on the screen display, you might have a problem with your LCD display or the lens cover might be on. Look back at the Troubleshooting Page on this device. It should have a dedicated page to fixing your problem.
If your camera is still not turning on, it could be a number of things that are not working. Refer to the Troubleshooting Page on this camera, it has answers to most common problems on why the camera won't turn on