This writer rejected employer's raise in relief (6)
I believe the answer is:
Here is my best explanation:
'raise in relief' is the definition.
(I've seen this before)
'this writer rejected employer's' is the subsidiary indication.
'this writer' becomes 'me' (the person who is writing these clues**).
'rejected' is a reversal indicator.
'employer's' becomes 'boss' (boss is a kind of employer).
'me' in reverse letter order is 'em'.
(Other definitions for emboss that I've seen before include "Carve or mould a design to stand out in relief", "Mould or carve in relief", "Produce raised design", "Make a raised carving", "Carve etc so as to raise from surface", "Decorate with riased design", "Raise (a design) in relief", "Print in relief", "Carve figure in relief" and "Make a raised design on".)