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