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