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