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