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