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