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