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