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