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