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