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