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