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