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)(11,22,25,36)(12,17,24,31)(13,18)(14,19)(15,21)(16,20)(23,32,38,37)(26,40,39,30)(27,33)(28,35)(29,34)(1,3)(2,6)(4,7)(5,8)(9,11)(10,17,20,31)(12,15)(13,26,28,39)(14,24)(16,25)(18,32)(19,22,21,36)(23,27,38,29)(30,34)(33,40)(35,37)(1,4,5,2)(3,7,8,6)(9,12,14,25,16,24,15,11)(10,17,21,22,20,31,19,36)(13,26,29,38,28,39,27,23)(18,30,33,37,35,40,34,32)(3,8)(6,7)(9,13,16,28)(10,18,20,35)(11,23,25,38)(12,26,24,39)(14,29,15,27)(17,30,31,40)(19,34,21,33)(22,37,36,32)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.