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