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