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