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