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