What is a mandala? According to the BBC website, it is a symbolic picture of the universe that is used in Tibetan Buddhism during meditation. Mandala is the Sanskrit word for circle.
This Instructable will be easier to follow if you have a basic knowledge of photo editing software. You will need to be able to remove the background from a photograph to leave just the image you want, duplicate it, re-size it, copy it, move it, rotate it and create mirror images by flipping it. You will also need to be able to select colours from images to create a background with a colour gradient, and you must be happy about working with layers. There are plenty of tutorials out there on the Web if you need help with any of the above that goes beyond the instructions I have provided, which are based on the Gimp v2.6.11.
What you need
Photoshop, the Gimp or similar image-manipulation software
Suitable digital photos you have taken, or copyright-free images from the Web