1st, call a groomer, it should cost less.
2nd, even if a cat goes outdoors, the nails should be trimmed (they can grow back INTO the foot pad. NOT a nice sight)
3rd.........get help. 4 hands are better than 2.

tips:
-do one, give a treat, let cat go. repeat later.
-let your helper scruff the cat's neck. You can get a LOT of control that way.
-be firm and be quick.
-allow the cat to be comfortable, they will fight less when comfortable than if they are in an unnatural position.
-bring them to PA, I'll do them (just a little humor)