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