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