You can tell the film is finished when auto winding stops suddenly before the film is completely wound to the next frame. Check the frame counter to make sure all the frames have been exposed.
DO NOT open the back cover until you have rewound the film
Firmly press in the film rewind button on the bottom of the camera. Once you have pressed it, you may immediately withdraw your finger.
Push the power rewind switch. The film will rewind automatically as long as you push this switch. During rewinding the frame counter will count backwards and the auto-winding lamp will glow and the film transport indicator will move.
DO NOT touch the shutter button while rewinding the film.
When the frame counter reaches "S" let go of the rewind switch. Open the back cover and remove the film cartridge.
Should the auto rewinding stop before the frame counter reaches "S", load new batteries, then continue to rewind.