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