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