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