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