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