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