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