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