Help 3Rd Class Transfer

Suppppppppppp  O0 need some help ive putted 1st and 2nd marks to shop and need to put some for 3rd but cant find mark or something like this how to add option to change 3 class for X adena, btw 1 and second like third are make in multisell im on l2j, or maybe how to add to gm shop button like in class master just for 3rd class

Edited March 23, 201511 yr by Rismok