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