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