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