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