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