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