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)(11,23)(12,28)(13,31)(14,21)(15,20)(16,22)(17,26)(18,30)(19,32)(24,35)(25,40)(27,39)(29,36)(33,38)(34,37) involution — undirected(2,5)(6,8)(9,11,14,26,16,27,15,29)(10,17,20,23,22,36,21,39)(12,24,30,13,25,32,34,33)(18,19,28,31,37,35,40,38)(9,12)(10,18)(11,24)(13,26)(14,30)(15,34)(16,25)(17,35)(19,36)(20,28)(21,40)(22,37)(23,38)(27,32)(29,33)(31,39) involution — undirected(1,3,4,7)(2,6,5,8)(9,13,14,32,16,33,15,24)(10,19,20,31,22,35,21,38)(11,25,26,34,27,12,29,30)(17,28,23,37,36,40,39,18)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.