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