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