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