Step 1. Open our photo.
Step 2. Proportion is the trick in this tutorial. To get perfect edges we have to make an ideal proportion between weight and height. Because of this we'll first make our brush. So go and pick Brush tool (press B on the keyboard), and go to the Toogle the Brushes palette.
Set values for our new brush exactly as I did (size of our brush is 20px and spacing is 120%; this gives us a brush that is 24px wide).
Click on Create new brush and call it as I did (or whatever you want, just remember it).
Step 3. Now, pick Marquee tool (M) and set Style to be Fixed Size and enter 768px for Width and 528px for Height. Right now you are asking yourself "Why these values?". As I said in Step 2 our brush is 24px wide so 24*32=768px and 24*22=528px. You can combine any value that you want but it must be 24px times some value (24 is our brush size). Now, click on canvas, set selection where you want it to be and go to the Image - Crop and press OK.
Step 4. Copy "background" layer by pressing Ctrl + J. Name new layer "postal_mark". Now we have to size up our canvas. Press Ctrl + Alt + C and enter these values for our new canvas. Leave anchor as it is.
Create new layer and call it "white".
Put it below "postal_mark" layer and you can now delete "Background" layer because we won't need it any more. Pick Paint Bucket tool (G) and fill "white" layer with white color.
Step 5. Pick Eraser tool and select brush that we made in our Step 2.
Step 6. Press and hold Ctrl on keyboard and click on "postal_mark" layer. This will select whole layer. Now click on Paths palette and click on Make work path from selection.
Now our selection is transformed to path. Click on arrow in top right corner of Paths palette and select Stroke Path.
Select Eraser tool and uncheck Simulate pressure.
Click OK. Hit del to erase Path.
Step 7. Pick Marquee tool and make selection inside "postal_mark" layer. Make its distance equal from edges of layer. Invert selection (Select - Invert selection), pick Magic Wand tool, press and hold ALT and click on white surface inside selection. This will select only edges. Fill selection with white (Ctrl + Backspace).
Step 8. Deselect by pressing Ctrl + D. Right click on "postal_mark_ layer and select Blending options.
Set values for Drop shadow and Stroke as I did.
Step 9. You can add some text to postal mark if you want.
See you!
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