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