Have you tried gently wrapping the in a towel with just one paw sticking out? Try to catch them when they are sleepy, do just two maybe three nails at a time.
Ask your friend for her secret.She'd scratch me a lot more if I tried to wrap her in something. It'd be easier to trim her nails than do that. Today, using the surprise factor because I had never done it before, I managed to trim one nail. Then later when I came to just manipulate her fingers, she knew better and swatted at me.
I had forgotten that my friend and the vet can trim her nails with no problem at all. I'm the useless one.