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