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