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