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