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