Kaleidoscopic effect.

Today I'll show you how to create a very simple and interesting effect. You can use it as a background or a banner.

Step 1.
Open a picture (or your photo). Duplicate a layer. Turn off a background layer.

Apply Image > Rotate Canvas > Arbitrary (Angle 45, CW). Choose the Rectangular Marquee Tool and make a selection of the unnecessary part and delete it.

Apply Image > Rotate Canvas > Arbitrary (Angle 45, CCW). Apply Image > Trim... with the following settings: Top Left Pixel Color - ON, Top - ON, Bottom - ON, Left - ON, Right - ON.

Step 2.
Then copy the layer (Ctrl+A) and (Ctrl+C), open a new document (Ctrl+N), and paste it (Ctrl+V). Now apply Image > Canvas Size with the following settings (increase the width in two times):

Step 3.
Duplicate Layer 1 and transform copy layer using Edit > Free Transform (Ctrl+T).

Step 4.
Apply Ctrl+E to merge down two layers. Now apply Image > Canvas Size with the following settings (increase the height in two times):

Duplicate Layer 1 and transform copy layer using Edit > Free Transform (Ctrl+T).
Merge down two layers, copy a layer and rotate it by 90. And that's it.