I'm using a Canon EOS Rebel X S 35mm SLR What setting should i set my camera for a manual shutter speed?

If your camera is a Rebel XS you should have a dial on the top right with a series of letters and icons. To set your camera so you manually control the shutter speed turn this dial too "TV" (Time Value). This setting will allow you to select the shutter speed and the aperture will open or close to achieve the correct exposure. The "M" is (Manual) where you would select both the shutter speed and aperture "AV" is (Aperture Value) where the user selects the aperture they want and the shutter speed increases or decreases to obtain a proper exposure. The "P" (Program) mode allows the camera to automatically select the shutter speed and aperture