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