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