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