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