1.photoshop cs6.0 Open the wallpaper image. Unlock command. Otherwise, it can't be operated in the future.

2. Select the rectangle tool and select the area to mark.

3. Select an area, that is, the location where you want to add a box, which is indicated by a dotted line. Look at the picture. This step is over.

4. On the right side of the menu bar above, select Fixed Size. Then fill in the size you want. Ps is good, you can choose the size at will.

5. Right-click the selected area and select Stroke. Fill in the data as shown. My picture is only 500x350. If you want the box to be thick and the picture to be big, you should write the pixels bigger. Choose red.

6. Then deselect. If you don't deselect it, many subsequent operations can't be performed (assuming that you continue to process pictures).

7. If you don't want the box to be so monotonous, you can. Go back to step 1 and select the ellipse tool to ellipse the box.