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