Follow these given below steps to print self item remark on bill format:-
Go to Master > MargSetup > Self format > Feed password as reverse format(yy/mm/dd) >Select invoice format-98 [DMP]/99[GUI]
Format window will be appear > Feed format name > Bill Format > Item > Press F1 key > Search "Self Remark"> Select option of "Item self remark <SB_SLFREM1,35>" Press Enter key.
Now Press F3 key > Use command (SB_SLFREM1,35) >Press Ctrl+W > Click on Save > Press Esc key to Exit.