Add Borders in photoshop

Add Borders in photoshop
1. Image > Canvas size > ADD  .5 & .5
   Click ok
2. Select the Background color
3. You can add one more color again Image > Canvas size

1. Image > Canvas size > Add .5 & .5
2. Rounded rectangle tool, make sure Path is selected and Radius 100px
3. Paths (windows pasth) load path as selection from ... round
4. select > Inverse
5. select > fill with foreground color

1. Duplicate layer
2. Image > Canvas size > 2 & 2
3. Style > Layer Style > select drop style
 Size 100px, spreadd, distance & Opacity 60
4. You can drag the drop shadow 

Source: https://www.youtube.com/watch?v=YsdsxZeRQ-Y