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