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