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