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