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