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