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