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