In case of protective rooster start talking in a low, friendly tone to your chickens even before opening/entering the coop, so they will know it is you and not a predator.
Use a small head light when grabbing the chicken from the roost and bring it in your house do he will not know what is going on.
When grabbing the chicken put one hand on her back, the other underneath her body. Or grab with both hands both her sides while at the same time fixing her wing tips to prevent her from flapping them in your face.
The nail clipping is done best while sitting on a kitchen chair and having the bundled up chicken laying on her side on your lapRight! Thanks