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