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