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