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