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