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