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