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