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