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