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