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