If you know how to use White-Out, you already understand the concept behind Photoshop's Clone Stamp.

How do you use White-Out?  You see an error on a typed page.  You daub the little brush around in the bottle, then you use the brush to daub the white stuff on top on the error to cover it up.

The only difference in Photoshop is that instead of daubing the little brush around inside the bottle, you first daub it at some part of your image - usually called the "source".  Whatever color/shade/part-of-the-image you've chosen as your "source" is the color/shade/part-of-the-image that will be used to paint over the "error".

Here's how:

Click on the Clone Stamp Tool.

Look up at the settings in the Option Bar.  You can experiment with a larger or smaller "brush".  You may also want to UNCHECK "Aligned".  ("Aligned" tells Photoshop, as you paint over a large "error", to keep moving the "source" point in order to keep it exactly the same distance from the error as when you began.  Sometimes you want this.  Most often you do not want it.  If you are not expecting the behaviour, it can be quite puzzling.)

Press and hold down the ALT key.  As you hold down the ALT key, click on the part of the image you have chosen as your "source".  This is usually called "selecting the source".

Release the ALT key.

Begin dragging the cursor over the "error" in a "rubbing" motion.  If you are covering a large "error" you will still note some of the "Aligned" behaviour, even with the Aligned option unchecked.  Just reselect the source area, and "rub" some more.

As you practice cloning, you will become aware of subtle differences in colors, textures, and shades, and you will realize you may need to reselect slightly different areas of the source periodically as you work, to match slightly different shades surrounding the "error" you are covering.

These instructions refer to the Windows version of Photoshop Elements.

Scott Kelby has an detailed cloning tutorial in his book, "The Photoshop Elements 5 Book For Digital Photographers".  The tutorial is titled "Cloning Away Unwanted Objects", and it begins on page 268.

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