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