Difficulty level: 
Meaning of colors: menu path, keyboard shortcut
Fixing torn photos
Used graphic application:
Adobe Photoshop 7.0
When moving the cursor above the image on the left - the image before the processing appears.
Before you start working with Photoshop - you have to scan a torn photo. Place its two parts on a scanner glass so their edges are parallel to each other. It is the best to move them to the edge of the glass so they look like a photo but with one centimetre long space gap between two parts of it.
When you have the torn photo scanned - let's start.
1. Open the Photoshop.
2. Open the photo purposed to processing:
Choose File » Open from main menu, or press Ctrl + O keys
...or by double clicking the left mouse button on the dark grey application background.
3. At the beginning let's remove the white gap between fragments and copy what's left (it means parts of the picture) to the new layer.
Choose the Magic Wand 
(W) from toolbox. In the tool menu set the Opacity value to about 15%.
Click at the white gap between photo parts with the wand. As it is in a colour of a scanner cover (white usually) - the wand should outline the whole gap without any problems.
If your picture has some light colours near the edges the wand can outline these fragments as well. It is not a good situation. But there is a solution. Before you scan your photo - cover it using the sheet of one-colour paper in colour that is not in the neighbourhood of edges of the space gap. It will be easier to cut it out then.
4. The space gap is selected - preview.
Now we have to invert the selection. It is the way of creation of the selection of the photo parts. For that purpose choose: Select » Inverse from the menu or press Ctrl + Shift + I keys. That's how we selected both fragments of the photo - preview.
5. Now copy them and paste to the new layer: press Ctrl + C, then Ctrl + V. The new layer appears:
6. We're working on the new layer now.
Before we move on - grab the lower right edge of the photo window (cursor turns into the little arrows) with the cursor and enlarge the work area, by dragging it 1-2 centimetres slantwise in the right down direction. You can also click the maximization icon that is in the blue bar of the photo (little square).
Choose the Rectangular Marquee Tool 
(M) from the toolbox. Use it to outline one of the photo parts (it is desirable that is was the one which is better cut out so has less white colour near and on its edge).
Locate the cursor between photo parts in the grey work area above the photo. Click the left mouse button and still holding it - drag outside the opposite lower edge of the photo part. Selection won't reach outside the edge anyway so we have more accurate selection doing it that way.
We obtain something like that:
Copy it and paste to a new layer: Ctrl + C, then Ctrl + V
In the layers bookmark appears the new layer:
We're working on it now.
7. Choose the Move Tool 
(V) from the toolbox. Using it shift the selected fragment to the second. You can use the keyboard arrows if that helps. It is the best to do it with a large zoom (it is the most precise way).
As we see there is a white line in the shape of the gash. That are the remains of the gap cut out (step 3). We will try to remove as much as possible of it using rubber. Do it in a large magnification.
Choose the Eraser Tool 
(E) from the toolbox. In the tool menu set the following properties:
Now erase the white remains precisely and carefully. If you erase too much in any step - undo that last step by pressing: Ctrl + Z keys. The gap is still noticeable but less - it is a good basis for the further work - preview
The hardest part is coming right now.
8. Choose the area on the right (left) side or the gap (usually a few millimetres from it) in the point which colour and texture is like it should be in the gash. Move the cursor to that location and press the Alt key. The cursor turns into a viewfinder - click the left mouse button. Release the Alt key. That's how we select the area from which the picture is to be cloned. Now move the cursor (circle) above the gap remains. Click the left mouse button and paint over these remains (like using the brush). Instead of paint (colour) we paint using the picture copied from the place which we marked to clone from. The little cross next to the cursor (circle) indicates that place of cloning in the current moment.
Simple rule: Alt key pressed - cloning, Alt key released - drawing.
It is not an easy technique and it requires some training. You have to practise some time with that tool to get into stride. The place from which you are cloning picture and the place to which you are moving it are both important. The best way is to use natural lines, colours boundaries and similar paths. In areas that are colourful and full of details - do it using big zoom, with single mouse button clicks.
If you successfully plough through that step - congratulations :) We can go to the last stage that is cropping.
9. Choose the Crop Tool 
(C) from the toolbox.
Place the cursor precisely in the photo corner, click the left mouse button and holding it - move it exactly to the opposite corner. Release the button. As you can see the program creates the frame. Everything what is besides - is to be cut out. You can still correct its dimensions - by dragging with the mouse these tiny squares in the middle of its edges. When everything is OK - press Enter or click the tick on the right part of the submenu.
And that is it.
If you liked that tutorial - I recommend you to see it on the film, where you can see from where I clone the picture, depending on the area of a current operation.
Using the Clone Stamp Tool is also described in tutorial: Removing objects from photos
photomontage
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photo retouch
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Picture in sepia