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