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