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