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