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