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)(25,26,30,32)(27,37,38,39)(28,34,33,40)(29,36,31,35)(1,2)(3,7)(4,6)(5,8)(9,11,13,18)(10,14,16,17)(12,19,21,24)(15,22,20,23)(26,32)(28,33)(35,36)(37,39)(1,3)(2,5)(4,8)(6,7)(25,27,29,40,30,38,31,34)(26,33,35,39,32,28,36,37)(2,6)(3,8)(11,18)(14,17)(19,24)(22,23)(25,28,30,33)(26,34,32,40)(27,36,38,35)(29,37,31,39)(2,6)(5,7)(9,12,13,21)(10,15,16,20)(11,19,18,24)(14,22,17,23)(25,29,30,31)(26,35,32,36)(27,34,38,40)(28,39,33,37)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.