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