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