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