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