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