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