Some time back for my Lotus Flower project, (still ongoing after all these years. See http://100lotusflowers.blogspot.com) I stumbled upon Islamic Design and Sacred Geometry and bought the book above to assist in the exploration of this topic. (I love the sacred meanings behind all the elements of Islamic Art, but that's another blog post)
To begin the patterns you must first construct a series of geometric shapes, and then proceed to mark out a pattern behind the pattern, or between the pattern that is before. It has been a challenge for me and I have not quite been able to get the formular.
The patterns require you to "See Beyond the Veil" of what is obvious in front of you. You can create exciting patterns like the one below; which I noticed shows up in a lot of home decor. I noticed it on the set of Being Human,
On the Landing
If you are looking.