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