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