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