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