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