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