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