You don't want to edit your original file—and save the edited version—over the original.
You want to preserve the original file.
When you save your edited photograph, Photoshop Elements will save it using the Photoshop file format, by default.
You'll have two files on your hard drive.
1) Grand_Canyon.jpg—your original
2) Grand_Canyon.psd—the edited version
Your original file is preserved.
If you need to save the edited photograph using the JPEG file format, preserving the original becomes a little more complicated.
When you save a JPEG file as a JPEG, Photoshop Elements will append the word copy to the file name.
Your original file is preserved.
1) Open the photograph you want to edit.
2) Go to File > Duplicate.
Photoshop Elements will open a duplicate of the photograph with the word copy appended to its name.
3) Close the original.
4) Edit the copy.
Your original file is preserved.
1) Open the photograph you want to edit.
2) Go to File > Save As.
3) Change the file format from Photoshop to JPEG in the Format box.
4) Rename the photograph by adding _copy or _edit to the end of the file name.
3) Click OK.
4) Edit the copy.
Your original file is preserved.