Post your mirror shots here. You must take the original image from your camera and mirror it in Photoshop, or whatever editor you use. No reflection shots allowed. If you don't know how to do it, read on. There are probably other ways to do this. I'd like to hear if you have a better method. Flowers can work well, also some group people shots - the 'best' side of your partner mirrored to make them perfect all over! But you may need to avoid hairlines as it won't look symmetrical.
1. Take a shot (that was easy!) It often helps to get the subject at an angle to get a freaky shape.
2. Edit image in normal way - exposure, colouring, cloning etc. You may need to crop the shot first to get a suitable join line.
3. Select all of the image and copy - CTRL/A and CTRL/C in PS.
4. Go to canvas size in PS and double the width or height (but only one of them, depending on the orientation you need). You need to specify just one side for the size expansion. Your shot will now look something like this...
5. Do a paste of your previous selection (CTRL/V)Your paste will create a new layer. It will now look like this...
6. With the layer selected, go to EDIT/TRANSFORM/FLIP HORIZONTAL. Don't use IMAGE/IMAGE ROTATION or you will flip the whole shot, which you don't want. Move the flipped layer and reposition it to the left/right, or whatever until the edges align. If you exactly doubled the canvas size this should fit perfectly. The finished result should be like this...