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