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