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