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