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