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