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