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