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