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