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)(25,26,31,29,32,35,30,34)(27,36,38,37,33,39,40,28)(1,3,5,4)(2,6,7,8)(9,10,13,14)(11,18,17,15)(12,21,20,16)(19,22,23,24)(25,27,32,33)(26,28,35,37)(29,39,34,36)(30,38,31,40)(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)(26,33)(27,35)(29,40)(30,39)(31,36)(32,37)(34,38)(10,14)(11,17)(16,21)(19,23)(25,29,30,26,32,34,31,35)(27,37,40,36,33,28,38,39)(9,12,13,20)(10,16,14,21)(11,19,17,23)(15,22,18,24)(25,30,32,31)(26,34,35,29)(27,38,33,40)(28,36,37,39)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.