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