First, check that there is a reset button located on the camera then take a pointed object (such as a pencil or paperclip) and press down on the button. Hold the object down for 3 seconds and then release.
First, check to see if your camera needs needs to be re-charged. If your camera's battery was fully charged and the camera is still not turning on, slide the battery cover off to pop out the battery. After ordering a new battery, insert the new battery into the battery slot and turn on the camera.