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