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