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