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