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