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