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