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