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