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