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