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