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