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