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