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