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