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