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