Photoshop : Kaleidoscopic effect

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.