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