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