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