1. The clone stamp tool does not "clone out." It superimposes donor pixels over a designated locus.
2. On the tool's option bar, be sure that opacity is set to 100% & that "Sample all Layers" is checked.
3. Adjust your cursor so that it embraces the source (donor) pixels. For example, if you wish to place an orange on an apple tree, adjust the cursor to include the orange. The keyboard shortcut(s) for this are the bracket keys next to the letter P. [ smaller, ] larger.
4. Hover over the orange and press the ALT key on the keyboard, then left click on the destination for the clone - the apple tree in our hypothetical.
5. I like to place the clone on a separate layer, so that I can delete it if things don't look right, and I can start over. Open a blank layer above the Background layer to facilitate this.
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