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