LOL, long story to tell but I "learned" to trim them "hard way".
I'm sure your friend can do it, too.
First few months - I got bitten, scratched, hissed(and then either bitten or scratched after that)...you name it, Ku Ku did anything and EVERYTHING to me to avoid it.
Then, I learned a couple of tricks for "happy medium" for both of us
1) Start "one at a time" when cat is in either sleepy or relaxing mode.
Try trimming 1, 2 or just as many without scaring him/her off. If she/he resists it or freaks out, stop immediately.
2)Do not even try when he/she is fully awake & alert, or in a playing mode - the chance is...ouch...
3)Although, I don't know if this works for every cats, I always give Ku Ku a little "treat" ONLY IF she lets me trim them(that is, without resisting or biting). I also praise her for being "a good girl" before giving any treat.
Besides trimmers, I've 3 different scratching posts - 2 verticals & 1 horizontal(to lay on a floor), which she uses whenever she feels like it.
There's several different kind of trimmers to try, too. My sister used regular nail-clippers(for human beings) for our family cats. I use scissor type trimmer for Ku Ku as she "resists more" than our family cats.
I also purchased a pedipaws, hoping it'd work as the TV commercial claimed it would, but Ku Ku never got used to it. She got scared off everytime I took it out and turned it on
I got 2 friends of mine who purchased it, too, but they both said the product did not work the way it advertised either.
Sorry for changing the subject but just FYI.