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