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