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