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