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)(11,20)(12,16)(13,17)(14,18)(15,19)(21,22)(23,24)(25,26,30,31)(27,29,34,32)(28,36,38,33)(35,39,40,37)(1,3,5,8)(2,6,7,4)(11,12)(16,20)(21,23)(22,24)(26,31)(27,34)(33,36)(35,40)(1,3)(2,4)(5,8)(6,7)(9,11,15,12)(10,16,19,20)(13,21,18,23)(14,22,17,24)(25,26)(27,32)(28,33)(29,34)(30,31)(35,39)(36,38)(37,40)(1,4)(2,3)(5,6)(7,8)(9,12,15,11)(10,16,19,20)(13,23,18,21)(14,22,17,24)(25,27,30,34)(26,32,31,29)(28,35,38,40)(33,39,36,37)(9,13,15,18)(10,17,19,14)(11,21,12,23)(16,24,20,22)(25,28,30,38)(26,33,31,36)(27,35,34,40)(29,37,32,39)(9,14,15,17)(10,18,19,13)(11,22,12,24)(16,23,20,21)(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.