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