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