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