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