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