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