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