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