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