Instructions
Turn on your home computer, connect to the Internet and download the program you want to use. Adobe Photoshop has to be purchased, but does have a free trail. Paint.net and GIMP are free programs.
Open the program you just downloaded. Click "File" and select "Get photo," or open from the drop-down menu. Locate and click the file of the photo from which you want to remove the shine. Click "Ok" in the bottom-right corner of the box to open the picture.
Click the small "Band aid" icon in the left side margin. This is called the "Spot Healing Brush" in Photoshop and has similar names in the other programs. You can adjust the size of the tool in the settings window across the top of the program when it is opened. Adjust the size of the cursor, so it just fits over the shine you want to remove.
Click the mouse button when you have positioned the tool over the picture. The program will remove the portion of the picture encompassed by the tool, and replace it with similar information from the surrounding area to rebuild the picture. This works well for small parts of the picture you want to change. For larger areas, you will need to work in stages, removing smaller portions of the affected area until it all is replaced.
Click "File" and select "Save as" to give your edited photo a new name and save it to your computer. By saving it as separate file, you retain the original for future editing work.