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