You can make a kaleidoscope with any photo and to show you how even a bathroom can be turned into an attractive image I am going to choose this photo

which you might think looks a bit boring!

So open your chosen photo in Photoshop.

We now need to make a triangular selection, which involves in the first instance Making a square selection.

So choose the rectangular marque and hold down Shift while you draw a square.

Remember that the bottom line of your square will be the outside edge of your finished kaleidoscope.

Mine now looks like this

Now go to 'Select' and 'Transform Selection'

This will give you 'handles' at each corner of your selection. Right click inside the selection and choose 'Skew' from the drop down menu.

Put the cursor on the top right 'handle' and drag it down to the bottom handle. On the top attributes bar on the right hand side you will see a degree box which when you start will be at 0. This must be 45 degrees exactly or it will be difficult to line up the finished triangles. I have found that this is easier if you enlarge the image as much as your screen will allow at this point to be accurate.

This is my finished triangle so press enter and the transformations will be saved. You can make adjustments at this stage as to exactly what part of the photo you choose by using the 'Move' tool to reposition your triangle.

Next go to 'Edit' > 'Copy'.

Then to 'File' > 'New'. Do not change any of the sizes in this new document - the 'colour of the square is not important I usually choose transparent as I find the squares help with positioning.

When you have the new square document go to 'Edit' > 'Paste' and your triangle will be pasted into the new image.

So far so good.

Now the Canvas need to be bigger so that we can fit all the triangles on to it and form our kaleidoscope.

So go to 'Image' > 'Canvas size' > There will be a measurement probably in cms. Change this to % and take it to 200%

We also need to increase the size to the left of the present image and above it so where it says Anchor, anchor the image in the bottom right corner.

These are the settings you need.

And the result should look like this.

Now we need to Duplicate Layer - so that on the layers palette you will have two layers the same and a background layer. With the top layer highlighted right click in the middle of your image and choose Free Transform. The handles will again appear and in the centre point of the diagonal is a rotation point. Put the cursor on this point and move to the left till it slides on top of the point half way down the upright line.

When you have placed the central rotation point on the left hand middle handle then right click on the image and choose 'Flip Horizontally'.

You should then have a trangle scanning the bottom line of your canvas. Press enter to complete the Transformation.

You may need to use 'Move' now as I sometimes find that somehow a pixel seems to have gone astray and there is a tiny gap down the middle of the two uprights. But the image should look like this at this stage.

Discard your bottom Background layer and then Merge visible layers.

Duplicate Layers

Then go to 'Edit' > Free Transform.

This time move the central rotation spot to the apex (point) of the triangle.

Right click on your image and choose 'Rotate 90 degrees CW' , 'Enter' to Apply  the transformation

Again you may need to adjust this second triangle to remove spaces using the move tool.

You can see in the image above that there is a tiny gap at the far left where I have adjusted the triangles to fit.

When you are satisfied 'Merge Visible' and Duplicate Layer.

Go to 'Edit' > 'Free Transform' (nothing to move this time), right click on the image and choose 'Rotate 180 degrees'. And this should complete your Kaleidoscope. You may need to make some final adjustments and perhaps crop around the edge if like me you find there is a spare pixel or two!!

This is the finished Image. Hope you enjoy doing it!!