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