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