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