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