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