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