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)(25,26,31,35)(27,28,36,32)(29,33,37,40)(30,34,39,38)(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)(26,32)(28,35)(29,30)(31,36)(33,38)(34,40)(37,39)(2,5)(3,7)(10,11)(12,19)(13,21)(22,23)(29,37)(30,39)(33,40)(34,38) involution — undirected(3,7)(6,8)(9,11,14,10)(12,15,19,17)(13,18,21,16)(20,22,24,23)(25,28,31,32)(26,27,35,36)(29,38,37,34)(30,33,39,40)(1,3,4,7)(2,6,5,8)(9,12,14,19)(10,15,11,17)(13,20,21,24)(16,22,18,23)(25,29)(26,33)(27,30)(28,34)(31,37)(32,38)(35,40)(36,39)(1,2)(3,6)(4,5)(7,8)(9,13)(10,16)(11,18)(12,20)(14,21)(15,22)(17,23)(19,24)(25,30)(26,34)(27,29)(28,33)(31,39)(32,40)(35,38)(36,37) 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.