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