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