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