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