I love the look of pinch pleat curtains and often use clips instead of sewing. It is really easy to fake it and looks much better than clipping the panels to the top of the curtains.
Not to insult your intelligence, but here is how I do it. I'm sharing this because it took me a while to achieve a consistent pinch.
The fabric is gathered in the back and clipped. I wanted a two finger pinch which requires three creases on the back and creates two creases on the front.
As far as spacing, I've tried to do the math and sometimes come up a little short at one end or the other. So I just play with it until it looks right.
This way you do not see the clips at all only the rings. If you want a fuller panel just use two panels on each side instead of one.