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