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