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