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