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