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