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