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