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