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