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