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