The no sew kind requires a styrofoam ball, a box of strait pins & a bunch of fabric squares.
But you can get a lot of variation by changing the distance between layers & popping different colors or going tonal. Up to you!
Or using ribbon squares
Or this kind
Kimekomi swirl (call it what you will)
Blah blah blah
If you can sew - go to town!
Speaking of ribbon
I'm cutting back on the links because I doubt you actually click and you are perfectly able to google for yourself, aintcha? :)