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