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