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)(25,26,30,33)(27,31,35,29)(28,36,39,32)(34,40,37,38)(4,8)(6,7)(10,12)(14,16)(18,21)(22,24)(25,27,30,35)(26,29,33,31)(28,34,39,37)(32,40,36,38)(2,3)(6,7)(9,10,13,12)(11,16,15,14)(17,18)(19,22)(20,21)(23,24)(25,27)(26,31)(28,37)(29,33)(30,35)(32,40)(34,39)(36,38)(1,3,5,2)(4,7,8,6)(9,11,13,15)(10,14,12,16)(17,19)(18,22)(20,23)(21,24)(25,28,30,39)(26,32,33,36)(27,34,35,37)(29,40,31,38)(1,4,5,8)(2,6,3,7)(9,12,13,10)(11,16,15,14)(17,19)(18,22)(20,23)(21,24)(25,29,30,31)(26,27,33,35)(28,38,39,40)(32,37,36,34)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.