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