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