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