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