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