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