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