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