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