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