They are just made from tiny scraps from my fabric stash.
I have drawers full of colour sorted fabric and it's fun just to dip in and use some of it.
I use Bondaweb to secure the fabric to the backing piece and then machine in place.
A few hand stitches here and there and that's it. Probably an afternoon's work though.
My latest twiddler is intended as a Halloween themed one but, of course, I can't make them scary, so I went for a suitable colour scheme, pumpkin face, cats, buttons etc and a few twiddly knitty/crochet bits.