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