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