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