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