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