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