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