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)(12,20,22,21)(13,19,14,17)(16,24,18,23)(25,26,29,32)(27,30,34,37)(28,31,35,39)(33,38,40,36)(2,5)(6,7)(9,11,15,10)(12,21,22,20)(13,19,14,17)(16,24,18,23)(25,27)(26,30)(28,33)(29,34)(31,38)(32,37)(35,40)(36,39)(9,12,15,22)(10,16,11,18)(13,24,14,23)(17,21,19,20)(25,28)(26,31)(27,33)(29,35)(30,36)(32,39)(34,40)(37,38)(1,3,4,8)(2,6,5,7)(12,22)(16,18)(20,21)(23,24)(28,35)(31,39)(33,40)(36,38)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.