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