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