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