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