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