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