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