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