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