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