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