One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,5)(4,6)(7,8)(9,10)(11,17)(12,15)(13,16)(14,19)(18,23)(20,22)(21,24)(25,26,29,31)(27,32,33,28)(30,34,39,36)(35,37,40,38)(1,3,4,7)(2,5,6,8)(9,11)(10,14)(12,18)(13,19)(15,21)(16,17)(20,24)(22,23)(26,31)(27,35)(28,37)(30,39)(32,38)(33,40)(2,6)(5,8)(9,12,13,20)(10,15,16,22)(11,18,19,24)(14,21,17,23)(25,27,30,35,29,33,39,40)(26,32,34,37,31,28,36,38)(10,16)(14,17)(15,22)(21,23)(26,31)(28,32)(34,36)(37,38) involution — undirected(11,19)(14,17)(18,24)(21,23)(25,28,30,38,29,32,39,37)(26,33,34,40,31,27,36,35)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.