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