Spinner as insect is the imago stage of a mayfly. It's the true adult - the dun is mere adolescent. The male spinner gets away easy with just two tasks, Sex then Death, while the female adds a third: 'Lay eggs' to her To Do List (between sex and death). For both it's the ultimate snooze after the "Ohh, Ahh, Ohh ..." .
As fly pattern a spinner can be rather generic in materials, simple in coloring; not so much in profile. It has a dead man's floating profile which makes it killer in two ways, fish fooling and tippet twisting. The fly propellors when cast and forces the tippet to spin up onto itself, resulting in an unwanted side growth reminiscent of your favorite aunt's neck mole. Did I just ruin something for you?
The larger the spinner plus the finer the tippet equals the greater the growth (twist).
How to prevent? For me it's with the Surgeon's Swivel, merely a Surgeon's knot as a jam stopper - the end of the leader tied in a ball / fist large enough so it can not pass through the hook'e eye. The fly twirls around the ball, pivoting but not bringing the tippet with it. It's brilliantly simple. I first read about it back in the early eighties, in Art Lee's book, "Fishing Dry Flies for Trout on Rivers and Streams". Knock on wood, it has never failed me. Ever.
A common rigging for me is a size 12 or 10 spinner on 5x (.006) tippet. For that, marrying the 5x with a piece of 2x (.009) works well to form the Swivel's ball. Depending on hook eye size you may need larger, say 1x, or you may get by with less. Your call.
Illustrated below in big goofy learning form: