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