One vertex per element, one color per generator, with an edge from x to x·s.
(7,11)(8,10)(15,19)(18,20)(21,22)(23,29)(24,28)(25,26)(27,31)(30,36)(32,35)(33,34) involution — undirected(2,4)(5,6,9,12)(7,8,11,10)(14,17)(18,20)(22,26)(27,29)(28,34)(35,36)(1,2,3,4)(5,7,9,11)(6,10,12,8)(13,14)(15,18)(16,17)(19,20)(21,22)(23,27)(24,28)(25,26)(29,31)(30,35)(32,36)(33,34)(5,6)(7,10)(8,11)(9,12)(13,15)(14,18)(16,19)(17,20)(21,23,25,31)(22,27,26,29)(24,32,33,30)(28,36,34,35)(5,8,9,10)(6,11,12,7)(21,24,25,33)(22,28,26,34)(23,30,31,32)(27,35,29,36)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.