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