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