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