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