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