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