Grease on the clip? travel path of the pads?

I don't put grease or anti-seize between 刹车片与shims.  But other people do.  Did you put some grease or anti-seize on the retainer clip where it makes contact with the pads? or the edges of the pads?  pads need to travel on the clip freely.  I will post some internet pictures.

I also put some rubber like material on the back of the pads where it contacts the piston, to avoid the high pitch squeaky sounds.