Goodness me, this one was awkward. A combination of annoying shadows and cogs that I had to create manually made it a pretty time-consuming affair, and just when I thought the icon was done I put it in the Dock and it just didn’t look right. It took a fair bit of extra tinkering until I was happy with it, but here it is.
After a bit of deliberation I stuck with the System Preferences shape from OS X, and at first I had a rectangular section that contained the cogs. It just didn’t look right, though, so instead I used the circular design from iOS 7 and mixed it with the rectangle. I’m really happy with the final design, but I also considered that the circle at the centre of the icon would be a different size to the other circular designs from the project (like Safari, iTunes etc). Because of this, I also made a round version of the icon, so if you prefer to keep everything uniform you can grab it right at the bottom of this post.
As always, you can grab the other icons in my project below. You should also get hold of Candybar – you’ll need it tomorrow, because I’ll be redesigning the Trash icon and Candybar makes changing it much easier.