Without color; lacking characteristics which give variety. blank (Adjective). Free from writing, printing, or marks; having an empty space to be filled in; as, blank paper; a blank check; a blank ballot. blank (Adjective). Without expression.
Yes they do damage hair. Every time I have tried one ,I wound up looking like a Q-tip or my head looked like cotton. A perm will damage even more and look worse if you have been coloring your hair. There's chance of it looking okay if you don't color your hair.
There is an in salon treatment that can prepare your hair for a perm. This treatments can be done in the salon. This treatment should be done between 2-4 days prior to the perm but should never be done within 24 hours of receiving a perm.