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