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