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