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