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