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