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