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)(27,37)(28,30)(29,36)(31,35)(32,38)(33,39)(34,40)(9,11,13,19)(10,14,16,17)(12,18,21,24)(15,22,20,23)(25,27,31,38)(26,32,35,37)(28,34,39,36)(29,33,40,30)(1,3,5,4)(2,6,7,8)(25,28,29,32,31,39,40,37)(26,33,36,27,35,30,34,38)(9,12,13,21)(10,15,16,20)(11,18,19,24)(14,22,17,23)(25,29,31,40)(26,34,35,36)(27,33,38,30)(28,32,39,37)(1,4,5,3)(2,6,7,8)(11,19)(14,17)(18,24)(22,23)(25,30,40,27,31,33,29,38)(26,28,34,37,35,39,36,32)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.