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