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