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