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