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