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