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