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