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