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