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