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