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