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