One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,3)(5,6,9,7)(8,11,12,10)(15,19)(18,20)(21,22,26,25)(23,27,29,31)(24,32,34,28)(30,36,33,35)(5,6,9,7)(8,10,12,11)(14,17)(18,20)(22,25)(23,29)(28,32)(30,33)(2,3)(6,7)(10,11)(13,14)(15,18)(16,17)(19,20)(21,23)(22,27)(24,33)(25,31)(26,29)(28,36)(30,34)(32,35) involution — undirected(1,3,4,2)(5,7,9,6)(8,11,12,10)(13,15)(14,18)(16,19)(17,20)(21,24)(22,28)(23,30)(25,32)(26,34)(27,35)(29,33)(31,36)(5,8)(6,10)(7,11)(9,12)(13,15)(14,18)(16,19)(17,20)(21,25,26,22)(23,31,29,27)(24,32,34,28)(30,36,33,35)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.