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