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