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