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