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