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