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